Marten I think has just had a life collapse. there are times, when we think we have our lives in order and figured out, that when things change for the worse, we realize how little control we really have. Most people go through it sophomore year of college. A lot go through it in their mid to late 20's.
Marten has a dead end job, he's in a go-nowhere band, his silver medal girlfriend dumped him, and he's realizing that his "best friend" that he spend nearly a year fixing up is totally ready to sleep with other guys now. What does he lose by blowing up his life and starting over?
Originally, I was going to focus just on his relationship to Faye. What does he get out of it? What makes her valuable to him? In other words, in what ways would his life be worse if she moved out and never saw him again?
I'd imagine Marten is going to work on getting all parts of his life in order. That, or just use Sven and Tai's connections to start blazing a path through the local college girls.
And as for faye forgiving him, I think the problem isnt' what he said. The problem is that what he said was more true than false. And, not to sound like an apologist, but wouldn't Faye need to apologize for, I dunno, knocking marten out? I don't know about your circle of friends, but violence is worse than words.