I might be a little late with this, but now that you've gotten the "Alex" thing taken care of you can focus on "Mark".
This is my advice about Mark: Mark knows he might be transferring and becoming a brother. He also knows where he stands with Alex and his roommates. If I were you, I would think about leaving the decsion of whether to pursue or not mostly in his hands...of course you get some say, but if he feels it will work out fine, trust him. If he wants to give it some more time, if he's worth it, give him the time. I know these things can be hard to talk about, but if you can't talk about them then how can you have a relationship?
And congrats with Alex....alot of girls would have caved...good show
