"Sherlock, you in?" Greg called as he walked up the stairs. He heard a hum in response, and so entered the flat. Greg walked in and sat in John's chair, seeing as Sherlock remained curled up on the couch in his dressing gown. He clearly wasn't in a good mood.

"What do you want, Greg? Shouldn't you be at work, or compromising my brother?" Sherlock asked with a dead panned face. Greg laughed.
"Yeah, well, I plan on doing both of those things later. I wanted to talk to you first."
"Oh, lucky me." Sherlock groaned.

"So, what have you been doing lately?"
"Nothing. Bored." Sherlock griped, and turned so that his back was to Greg.

Greg frowned. He knew as well as John did that a bored Sherlock was a destructive Sherlock. He tried to lighten the mood a little.
"Well, the place is still standing, so you can't be that bored."

He got no response.
Well, might as well just say what I came to say.

"Sherlock, I wanted to talk to you about John. I know you're not coping very well without him around, and …no, don't try to deny it… and I want to tell you that I'm still here for you." Greg said, raising his hand to Sherlock when he'd turned around ready to spout off at him.
"I'm fine." Sherlock grumbled, his arms crossed as he lay on the couch.
"No, Sherlock, you're not. It's been a big change for you to come back, expecting things to continue on as usual, and find that everything's different. I know you; you don't like change."

Sherlock remained silent, although he was glaring at him furiously. Greg sighed.
"You're going to need to talk about this, Sherlock."
"No, I don't. You wouldn't understand anyway."
"Yeah, I think I do, Sherlock. I'm dating your brother, remember? He does talk of you, you know."

Sherlock bolted upright.
"What has he said?"
"Just things that I already knew or suspected anyway, relax."

Greg hadn't expected Sherlock to be so afraid of what he knew, or of what Mycroft had said. Was there more to it all than just what he knew?
Eh, that wouldn't surprise me. Damn Holmeses and their secrets.

"How do you feel about John not being here, Sherlock?"
"I don't want to talk about it."
"Perhaps, but I think you do need to."

Sherlock made a face that looked like he was struggling not to vomit, but then began to speak words in a hoarse voice.
"I … am not… comfortable… with his absence."
Greg nodded, and waited patiently for the man to continue.
"I had not expected to be alone once I returned. I had done enough of that abroad, and managed it with the expectation that I would come back to the enjoyment of his company once more."
"I know you care for him deeply, Sherlock. And that you wouldn't do anything to upset him - I am proud of you for that, you know. For avoiding the drugs even though I'd imagine you'd want them about now."

Sherlock shifted his gaze across the room, avoiding meeting Greg's eyes.
"John dislikes it. Smoking too… I noticed you went back on the patches once you and Mycroft worked out things. Did you know he smokes too? Not often but on occasion."
"Yes. I did. So you've stopped smoking too?"

Greg was trying to keep the conversation focused on Sherlock, who rolled his eyes at the question as if to say 'duh'.
"Good… I'm glad. You'll have to find something to occupy yourself with, though."
"Obviously."
"You could help out with the wedding?" Greg offered, deciding to just jump right in to the difficult things.
"I'm sorry?"
"John and Mary's wedding."
"I knew whom you were talking about, but I was merely incredulous as to why I should be involved?"
"Well… you know them both, I'm sure they'd welcome your input."
"Wedding planning is not my forte, and I believe it is supposed to be an activity between the engaged parties."

Sherlock's mood grew darker with resentment, and Greg knew he was on to something important.
"Sherlock, perhaps you should talk to someone about all this."
"But I am talking about this? Are you not someone?"
"I meant a therapist, but sure, I'm here to listen… if you start telling me your concerns."

Sherlock groaned again, and rubbed his face with his hands. He slouched forward, and mumbled something Greg couldn't understand.
"I'm sorry, what?"
"I said it's hard, Greg. It's hard to watch him go make a commitment to someone else. To see him make a new life, one that will inevitably be without me. Mrs Hudson's threats that marriage changes people and that they're going to just lose touch with me are eating at my nerves… but there's nothing I can do about it! I can't back away and let them have their lives, because I can't seem to stop feeling… I, I don't know, Greg. If I push myself unwanted into their lives, they're likely to reject me. I don't see a way to keep him."
"I think you underestimate how important you are to John."
"He has Mary now."
"Sherlock… he is capable of caring about more than one person at a time."
"Is he? It doesn't seem that way. He spent most of his life with me while he lived here, and then I leave and he attaches himself to you. Once Mary came along, you weren't in the picture anymore, and now that I'm back and he still has Mary, I'm not either."

Greg tried to come up with a counter argument, but Sherlock seemed to have a point.
"Sure, he might have a focus on only one person, but he still can have friends as well as a partner. That's just what happens. Friends aren't involved in a person's life as much as a partner is."

Sherlock made a face that told Greg he wanted to be the 'partner' again, not just a friend. Greg's heart drooped for the man, who sat across from him in a pitiful state.
"Sherlock… seriously, you should keep trying to be in touch with John. But I'm afraid that you're also going to have to accept that things are different now, and that you're just a friend to him now."
"What if I don't want to?"
"You'll only lose him more if you stay away."
"No, what if I don't want to be just a friend?"
"I'm afraid there's not much you can do about that, mate. Your choices now are just to do what you can to be a close friend to him, or to leave."

Sherlock sunk into himself and grumbled. They both knew what Sherlock would choose - there was no way he'd be able to willingly walk away from John Watson. Greg did feel sorry for him, though… stuck caring that much about someone who had already moved on, and never being able to leave to find that significant other for himself. But Greg had a feeling that Sherlock didn't care much for finding anyone else. At least he'd still be happy to have John in his life in any measure. He might just have to talk to John and Mary about including Sherlock more.

"How?" Sherlock whispered.
"How what?"
"How do I … be a good friend?" Sherlock asked, sounding defeated.
"I guess that depends on the situation. But I'll always be around to help you, you know that."
"Thank you, Greg." Sherlock uttered quietly, and laid back down on the couch with his arms wrapped around himself. He looked pretty traumatised, or overwhelmed, at the prospect of having to deal with all of these new changes. Greg just hoped he'd be able to help his friend cope with it all.

Greg felt like Sherlock needed some time to think about things on his own, and so he stood.
"Listen, mate, I have to go. Work calls. But you contact me any time, you hear?"

Sherlock just nodded absent-mindedly. Greg nodded, and walked out of the flat.
He's going to be thrilled - and a bit shocked - when John asks him to be his best man. Well, most likely asks him. I still don't know for sure.

That thought got him thinking - Sherlock would have no idea what that would mean. He was going to have to help him a lot with that. Realising he had to go to St Bart's soon for a case, he decided that he'd drop by Molly and ask for her thoughts on the matter. She might have a few ideas on how to help.