I might second the blog idea I don't think Sarah has done anything wrong, though I think she could helping out more with negotiating something that works for everybody, but she's kinda in the middle of a bunch of crazy turmoil herself, I'm sure its overwhelming.
I don't think John is a bad person, though I think he isn't acting nice right now because he is very focused on what he wants.
But I did ask about them taking a romantic (not friendship) break while everybody figures out what they want or need, and you don't want to address it (or address it here), so I'm not really sure that you are looking for input or advice, but more to talk things through and see if you can get any more clear about perhaps, what it is that you want to do about it all.
I wish you all luck though!
Happiness will never come to those who fail to appreciate what they already have.