I tried to do what I could with 4x23 and the beginning of 5x01. This is from Will's point of view and how I think he would feel for his brother. Leave me your thoughts.

Brothers Heart to Heart

Jay knew when they were called out to Bunny's his bad day was going to get worse. Not only was Erin facing the board, but now they had a Bunny problem to deal with.

After just barely seeing her before walking Bunny out, he knew she was going through a lot. But in reality they both had been for the last few weeks. Breakup that wasn't supposed to be a breakup, partner switches, and now all this... it would be a lot for anyone.

Hank sent him to the hospital to wait on an update for Martelli and get his statement. When he got there, he was more than glad to see his brother. He needed a sane voice in his spiraling day.

"It's surgery. They're pulling bullets out of the guy. It takes a minute," Will says as he keeps updating a chart. Jay paces and looks at his watch for the hundredth time it seemed like.

"I know. Its just ummm... There's a lot riding on this for Erin."

"She freaking out?" Will can't help but ask. Jay had shared over beers what had happened and he knew Jay was freaking out. His body language gave him away without their previous conversation about what happened.

"I don't know. We didn't speak really. I mean we couldn't. It's so messed up," he said frustrated.

Before Will can respond, Ethan comes out to let Jay know Martelli didn't make it. They discussed specifics and Will thanked him as he walked off. Jay appeared completely distressed now, so Will gives him an appraisal look trying to see where his brother's head is at. What came next totally took him by surprise.

"I want you to give me the key to mom's safety deposit box. I'm gonna ask Erin to marry me," Jay said completely serious.

Will could not helped the shocked look that crossed his face. Before he could respond, Jay continued with an explanation. "She's all I think about. She's been there for me every step of the way."

Will couldn't stop himself from questioning his brother. He saw things a little differently and clearly Jay wasn't thinking straight at the moment. "Why now? You two aren't even together. Are you?"

"No we're not, but she's in real trouble right now. I want to be there for her. I blew it once but I'm ready," he said trying to come off as determined as ever.

Will couldn't believe his brother in this moment. "Jay this girl does not want to be saved, okay? What you should be doing is putting some distance there."

Gurneys go rushing past and a paramedic informs Will of possible ods with more incoming. The timing is terrible since he's in a middle of a much needed heart to heart with his brother. His frustration was almost palpable.

"Go do your thing. Go!" Jay said clearly disappointed and heartbroken that Will didn't agree with him. Will slapped his shoulder giving it a squeeze before rushing off to work.
...
The case kept getting worse the longer they worked it. When Will showed up and Jay informed him of the missing pills and possible more ods, Will could see the fatigue in Jay's features.

He slipped the box out of his pocket and passed it to Jay. "Mom's ring. She always said it's not a race but whoever meets the right girl first gets the ring."

Jay shares a small chuckle as he stares at the box in his hands.

"You sure about this?" Will can't help but ask. He loves his brother and supports him, but this just feels all wrong and rushed.

Jay just gives him a look so Will pushes on. "You tell dad?"

"Why do I have to tell dad? It's mom's ring. It's not his," he says rather hatefully.

Once again they are interrupted, leaving Will completely frustrated with his brother. He definitely isn't agreeing with Jay on this, but at least Jay doesn't look totally heartbroken any more. Will gives him a last glance and heads back to the hospital to finish his shift.

Later when Jay sees Erin outside the district he feels hopeful that this will be their moment. He's even more hopeful when she asks if they can talk. However his hopeful moment is crushed when all she wants to do is talk the case she wasn't even supposed to know about. Before he can even say anything personal, much less get the ring out of his pocket, she's gone and he's left standing there like a fool. He puts it back in his pocket and heads in to wrap up this case that he's beyond done with. No matter how done with it he is though, he can't believe Hank is just letting the murder investigation go.
...
At Molly's later after shift, Jay is just staring off into space completely oblivious to the conversation flowing around him. He wants to know where Erin is and why she's not with them. Will can't help but watch him, totally worried for his little brother. Jay had already been spiraling and Will's not sure what this whole day is going to do to him.

"She'll be here," he finally offers knowing Jay needs to hear it.

"Yea. Give me a minute," he says taking his beer and heading out.

"Copy a minute," he hears as Will watches him walk off.

"That means a half hour," Will can't help but say as they others laugh. He drinks his beer staring at the wall wondering how he's gonna get Jay through this.

6 Months Later

It'd been a rough six months to say the least. Jay and Will were sharing an apartment, and while it was working out for them, Will was tired of giving Jay his space.

After that night at Molly's, his PTSD had gotten worse before it got better. Will had kept encouraging him to go to his meetings and open up to him, and while he went, it took almost three months before Jay was even slightly better.

Three months after Erin had left, Jay took a week and went to the cabin. He was getting better, but he just needed the final push to accept she was really gone. His repeated unanswered phone calls should've been his answer but they weren't. The week at the cabin seemed to do him good, and Will thought things were definitely finally looking up for him. He wasn't sure what happened at the cabin, but if his brother was getting better, he wasn't going to complain in the least.

Six months after she left, her previous landlord called Jay because she wasn't answering the phone. They needed the rest of the stuff out of the apartment so they could lease it again. Jay agreed to get it done wondering what all she had left behind.

He told Will he was gonna run by there. "You sure?" Will asked worried this would set him back.

"Yea... yea I'll be alright. She couldn't have left much," he shrugs. Will just nods as Jay heads out.

He'll never forget when Jay actually gave the ring back to put back in the safety deposit box. It'd been two months since Erin had left.

"Here... This... uh... This needs to go back," he said shoving the box into Will's hand.

"You sure Jay?" Will asked remembering how he'd asked if Jay was sure he wanted it.

"Yea," he said swallowing deeply. "She's gone Will. The uh... the apartment is cleaned out. She hasn't been at work... She's gone," he said a look of brokenness like Will hasn't seen on his brother before.

"I'm sorry man," Will said quietly giving Jay's shoulder a squeeze.

"Yea," Jay scoffed shrugging away from him.

"What's with the attitude Jay?" Will asked having gotten used to Jay's anger and outbursts over the last months since they'd moved back in together and Erin left him once again.

"You're sorry?! Cute Will! You didn't even want me to get it in the first place!"

"Jay... don't. You know it's not that I didn't want you to have it or y'all not to work it out. I just didn't think it was the right time is all."

"You know what I'm not doing this," Jay said before storming out. Will let out a sigh as he watched Jay leave again. It'd become a pattern with them lately and Will was at a loss.

That night when Hermann called him while he was on shift that Jay was way too drunk to drive, Will had left and gone and gotten him. That had become another pattern and he was getting sick of it.

The next day after Will pulled a double, he'd had it out with Jay that he couldn't keep falling into old habits and he needed to take his meetings serisouly to get better. Another month of the same shit and Jay finally started to get better.

Watching Jay struggle had been one of the hardest things Will had done. He wanted to help him but at the same time it was hard to help someone that adamantly refused the help. He just hoped that going to the apartment wouldn't be a set back.

An hour later Will's phone rang. It was Jay.

"What's up?" Will answered.

"Can you come over? Help me get the rest of these boxes?" He asked quietly.

Most of what was left was mutual stuff they'd bought together but neither took when they moved out. He would take the boxes of Erin's stuff to Hank so he could get it to her since he seemed to know the most anyways. The rest he'd have Will get rid of.

"Yea. Yea I'm on my way," Will said grabbing his keys.

He knocked and then called out for Jay as he pushed the door open walking in. It was totally empty as he walked through.

"Jay," he called again.

"Yea... bedroom," he finally called back.

"There's not much..." Will trailed off seeing Jay sitting in the floor staring at what appeared to be a picture in his hand.

"Na... I just... thought you could get rid of it," he shrugged finally glancing at Will. "That box goes to Voight. The rest... I don't care what you do with it," he shrugged again.

"What's that?" Will asked carefully sitting down beside Jay.

Jay turned the picture towards Will. It was a picture of the two of them not long after Jay had healed from his undercover kidnapping. They were quiet for a bit.

"It... It was face down under a box... in the closet," Jay said quietly letting it fall to the floor. "There's a whole box of pictures," he shrugged.

"You want them?" Will asked carefully. He had hoped Jay had started moving on, but now he wasn't sure. It felt time to have the heart to heart with him.

"I dunno," he said with a shrug. His head hung a little as his arms rested on his knees taking in the empty room filled with so many memories.

"Jay... I love you. You know that?" Will said nudging his knee to get him to look at him.

"Yea... I know."

"Then don't hate me for this. Just hear me out ok?"

Jay just barely nodded knowing he wasn't going to like whatever Will had to say.

"You gotta let go and move on. She clearly has... She left memories behind Jay... memories she obviously didn't want to remember for whatever reason. She left you once again. You gotta let it go."

"I left first," he shrugged trying his damndest not to get angry with Will.

"Yea you did. Did she fight to get you stay? Did she fight to get you to open up to her? Did she push you like you'd pushed her?"

Jay was quiet so Will continued. "Jay she didn't. She let you walk out that door. She let you put that distance. She didn't try. When you told her about meetings... what'd she say? She needed space? Why? She should've been willing to hear all about it and realize it's a step to getting better. But she didn't. She put as much distance as you did. I love you little brother, I do, and I know you loved her... but you gotta start moving on. She clearly has... quiet easily it seems."

Jay didn't have anything to say back to that. In a way he could see where Will was right and why Will felt that way, but at the same time he knew it was his fault for leaving first.

Will couldn't stop now that he'd started. It'd been six months of avoiding the topic so now he wanted to get it all out. "She left Jay. She hadn't looked back. She hasn't called. Hell she couldn't even take a few pictures. She left... left it all behind. And I know... It sucks to be the one left behind and you feel like you're shouldering all the blame. But this isn't all on you Jay. She made her choice... and it wasn't you," he finished quietly.

"Let's just get this done and get out of here," he said not making a single comment on Will's speech.

Will let out a sigh but nodded. He hoped what he had said to Jay would reach through to him and he'd start the process of letting go... Because he didn't deserve to shoulder all the guilt for her leaving nor did he deserve to keep hanging on to a dream that wasn't going to be.

Erin made her choice. She left. She left Jay and hadn't looked back. In Will's eyes that was a clear sign she'd never loved Jay like he loved her. And she damn sure didn't deserve their mama's ring now.

Jay grabbed a box and looked around at the rest. "I'm taking this to Voight. It's her's so he can get it to her. The rest... toss it all. Pictures too... hell... burn them for all I care," Jay said wiping at his eyes before readjusting his box. "I'll see you tonight Will. Thanks... thanks for this," he said offering Will his first real smile in six months.

"Of course buddy. You know I'm always here," Will smiled.

"Yea. Pizza and beer on me tonight. Have it waiting," Jay smiled before heading out. He left the key on the table and left Will with it. This was just another apartment to him now and it was time to start looking forward. Jay knew Will was right, but it took hearing it from Will to make him see it. Erin was gone. She wasn't coming back. It was time to stop holding on and move on. It hurt, but not as bad as it did six months ago. He was healing, and before long, she'd just be another chapter in his book, another memory that just helped shape him into the man he'd become. Nothing more than just a memory, he told himself as he walked out of the apartment for the last time.