"Are you headed over to Rossi's place?"

Aaron's head whipped around to focus on Penelope, and he fought to keep his face a neutral mask as he regarded her. "Why do you ask?"

"Erin mentioned that you were giving her guitar lessons, too, and I was hoping that you'd be headed there today. I made her this." She thrust a small package out at him, and he took it, not knowing what else to do. "She's not happy, Hotch, I can tell that much from her recent letters. And I know you're Rossi's bestie, but please, look out for her, too?"

"I'm trying my best," he replied, stepping back from her. "And I'll make certain she gets this."

"Thank you." She smiled, but it didn't seem to reach her eyes, and he knew that she was feeling the same way that he was about Erin. "Seriously, I don't want to cause issues in the team, but, well, I'm not even going to think about that. Go, now, before I really put my foot in my mouth."

He nodded a little, wondering what she had been about to say. Sighing, he turned and made his way over to the elevators. Dave had long since left for the day, and he wondered why he had taken off so early. Shaking his head, he tried to clear stray thoughts from his head as he climbed behind the wheel of his car, driving by rote to the Rossi home.

Rather than ringing the bell, he used his key to let himself inside, and set the guitar case on the floor so that he could hang his coat up on the rack. Before he could pick the case up once more, his attention was caught by the muffled sound of angry voices. Frowning a little, he grabbed the handle and made his way further into the house, looking around for the twins or their nanny. None of them were visible, which was small comfort to him, since he knew all too well that voices carried and could be overheard by little ears all too easily.

Letting out a shallow breath, he crept over to the study, the voices getting louder and louder as he approached. Aaron hadn't heard that much invective in his best friend's voice in years, and knowing that it was being hurled at Erin made him see red. Even when he and Haley were fighting so badly, he had tried to make certain that he never attacked her character, or how she looked.

"I've been more than patient, Erin! You've had two years to drop the extra weight from the pregnancy, and look how you used to look. Do you really think that I'll want…"

Aaron cleared his throat, getting Erin's attention, and as soon as the focus was off Dave, his best friend turned to look at him in the doorway. Dave's features were bright red, and he was breathing heavily through his nose, something that told Aaron he was very angry. "You seem to have lost track of time, Dave," he said flatly, hoping his tone of voice would help the man to back off Erin a little. She shot him a grateful look, though he couldn't acknowledge that without calling Dave's attention to it as well.

"It seems I have. Have a good lesson, Aaron. We'll pick this up later."

Dave brushed past him, and closed the door a little more firmly than necessary. Still, Aaron and Erin stood rooted to the spot, as if they were both listening for some signal that would tell them it was safe to breathe freely once more. Finally, that signal came in the form of the garage door opening, and Erin collapsed onto the couch, curling up into a tight ball as she obviously struggled to keep from sobbing.

"I wish that you hadn't heard that."

Her voice was gravelly, thick, and low, all things that clued him in to the fact that she was very close to losing it. He shook his head a little as he went over to the couch and sat next to her, reaching out and covering her knee with his hand. It was the safest space he could think of touching on her body, and still, he felt like he was toeing a very precarious line by doing that. "I'm glad I was able to stop it. I hadn't realized that things were quite this bad between you."

"We've always fought, Aaron. It's part of what makes our relationship so strong. And the makeup sex is pretty good, too."

Her voice had a different flatness to it than his had, and it broke his heart a little, so he tightened his hand on her knee, wanting to offer her more comfort. "You can only lie to yourself for so long. I think that we both know that to be true."

She shrugged a little, looking over his shoulder at the door. "If I can lie to myself enough, I can make it truth. That worked well enough when I was drinking."

"No, it didn't." She snapped her head to look at him, and he couldn't tear his eyes away from hers as she laughed lowly. "Erin?"

"What?" she snapped, and he deliberately allowed all his defenses to drop before he let go of Erin's knee, leaning in and wrapping his arm around her shoulders, pulling her close to his chest. "Aaron…"

"Just let go, Erin."

She shook her head, even as she curled up close to him, burying her face in his chest. It took more than a few breaths for her to finally break down, and once the floodgates were open, his shirtfront was soon soaked with her tears. "I love him, Aaron. So much. But there are people who would say that love isn't supposed to hurt like this."

"Those people are right."

Aaron felt every single bit of her hand as it spread out on his chest before curling in the fabric of his shirt. "But I will need someone who will stand by me, even as I stand by him. Please, stand by me."

He let out a deep sigh, knowing that he couldn't resist that sweet pleading in her voice, knowing that it had taken so much for her to be that open with him. "All right, I will. I won't like it very much, but I will. As long as you promise me one thing?"

"What?"

"Think about the way he treats you, and how it really makes you feel. There are people in this world that would support you, should you decide to make a change." She pulled away from him, and gave him a small smile before nodding a little. "All right, Penelope gave me a present for you, why don't you open it while I get my guitar out and tune it?"

"And then play the song you're going to work on with me?"

"Of course."

She gave him a quivering smile as he opened the guitar case and handed over the small square. Erin's hands caressed his almost thoughtlessly as she took hold of it. Aaron tried to ignore the fluttering of his heart as he picked up his instrument and quickly tuned it before starting to strum the chords of the only song that seemed appropriate in a time like this.

"When the night has come, and the land is dark, and the moon is the only light I see," he started to sing lowly, watching as Erin opened the package to reveal a delicately embroidered handkerchief. As she ran her fingers along the stitching, a pleased sigh slipped from her lips as she began to sing along with him. Setting the handkerchief aside, she picked up her guitar and began to strum along with his fingerings. It was remarkable, really, how well Erin was able to keep up with him, and he smiled a little to hear her voice join his in the song.

When they came to the end of "Stand By Me", he looked over at Erin, seeing tracks of tears running down her cheeks, and he knew that he had to do something to make her smile or feel a tiny bit better. "How are the twins? I take it they aren't here?"

She shook her head as she hugged her guitar close to her body as she continued to meet his gaze steadily. "David thought it would be best if they spend time with their aunt. It's only for another two weeks, but I miss my babies. If we're fighting this badly, however, it really is for the best that they're away."

"Do you get to talk to them at least?" he asked softly as he put his guitar in the case, never looking away from her.

Erin smiled a tiny bit as she nodded. "Bernice is quite good at making certain to call before they go to bed, and I read them a bedtime story. It's not as good as being able to kiss them to sleep or to tuck them in, but it will have to do until they're back in my arms again." She swallowed thickly as she darted her eyes away. "Aaron?"

"Yes?"

"Do, do I really look that bad?"

She had caught him flatfooted with her question, and Aaron slowly shook his head. "I think that you look beautiful just as you are. And if you want to lose weight, you need to make certain that you're doing it for yourself, not to make someone else happy. Okay?"

Erin nodded as she sank back against the sofa, still holding onto her guitar, strumming absently as she closed her eyes. "Thank you, by the way, for standing by me."

"Any time, Erin," he replied as he once more reached out to touch her knee, wanting the woman to know that his support would continue on as long as she needed it, even if Dave was his best friend. There were some things that were more important than friendship, and this was one of them.