Just a theory... don't take it for a fact:

I have a new theory in the light of the new sneak peeks and what we know about the rest of the season... have you noticed how the clips are overly light? In a Claire Obscure kind of way? (the adding of artificial lighting when it's not supposed to be there) I know the last few episodes have been dark but they are all seemingly sporting personal halos in the sneak peeks... what if the episode, or part of it, is a hallucination? I mean... Amber appeared in the saviours episode, House says it has been four days since he slept last, and still blames Amber appearing on his insomnia... which means only four days have passed since. Who would organize a bachelors party not even a mere fortnight after the engagement? That's senseless... and why would House do it? Isn't it innate to him to sit and sulk while others have a good time?

He's the one looking through the window at the things he won't let himself do. And why would he do this for Chase? They have a normal relationship, not that special... maybe everyone thinks he should have a party, so they ask House... which is no reason for him to do it. And House said the party would be "The day before your wedding" in the sneak peeks... where is this wedding in 5x23?

I think it's a hallucination, I really do. It explains Cuddy's and Wilson's concern, House's odd fragility and even Wilson checking up on him in the 5x23 promo pics. Maybe they find him in his office or something... and then he ends up getting checked over by Wilson and tended to at home by Cuddy.

Why?

Well... I personally think that there are a lot of unresolved issues between House and Wilson: Wilson left with the message that he didn't care that much for House, for what he did to try and save Amber and that it was House's fault she died... he returned with: "I guess we can't really choose who our friends are"... which does not undo that with which he left and to a guilt-ridden brain sounds like Wilson is apparently stuck with House.

Wilson has to this date never expressed gratitude for House's ultimate sacrifice, never told House that he does care and that House is as important to him as he really, really is... House is human too, he needs to hear those things and otherwise he'll carry the guilt around. The guilt of killing someone, really... and that's killing him in turn, but Wilson refuses to realize this. He still partially blames House for Amber's death... just look at his reaction to the Kutner suicide: he did not want to deal with House at all. If their friendship had been fully restored, that would be the first thing he'd do! But no, House has yet to become human again (to put it dramatically, but you know what I mean), and he does not grieve.

But he needs to, and Wilson has helped him, so they are slowly returning to what they used to be. That's why Kutner's death is having such an impact and Amber is back... Wilson doesn't even know how the whole affair changed House; he's only focussing on the effects it had on his own life... but House was changed dramatically too, and the guilt started to eat him and his self worth was gone. They need to talk, Wilson needs to apologize so House can heal, he needs to thank him for the deep brain stimulation (preferably from the bottom of... Wilson's Heart?) and realise just what an act of friendship it was, and he needs to tell House that Amber's death wasn't his fault... so that he can be back as not a friend, but the friend. Watson if you may... it's obvious that he's not fully back yet.

And, the last season finale, House risked losing it for Wilson. He dealt with the consequences without Wilson, the man he did it for. Now he fears he could lose it again and I think Wilson is going to be there now to keep him from going mad because this is the second chance... he's taking this one, he's going to get his own epiphany and maybe we'll finally get that bromance hug! House has been plagued by his guilt over what happened back then and it ate him slowly... Wilson's guilt (which he deserves to feel really, even though I love him dearly) will, when the genius is no longer the genius and the jerk is no longer the jerk so that what's left is just House, hit him in the face... and the man needs a wake up call.

I just think House feels somehow expendable in Wilson's life... the way Wilson nodded when House confirmed his plans of Deep Brain Stimulation... no wonder if he would! Wilson has been around since before the infarction, he knows House's brain is everything to him... but at that moment, he meant more. House didn't even hesitate.

Now, with House's brain on the line, Wilson will realize the importance of it, what he thoughtlessly risked. Now he'll appreciate it. Now it'll be House above all else, just like House put him above all else last season finale...

And then... they're back:

But if you try sometimes
you might find:
you get what you need