I too came to the US as a student in '99, met W and married same year when i was 23 and she was 21.
Since both us were so young and immature, our married life too went through lot of rough patches. There were a lot of dark times from mine and W side.
Until last year, i did find myself paying a lot attention to how i contributed to the demise. While that introspection was good, I also found myself to wallow in it.
If there's one big thing i learnt over last year, it is to recognize your mistakes, but don't relive them everyday. That is hell. Acknowledge them and move on and remember not to repeat them. If you do, then don't kill yourself over it. We are after all human. Personally i feel that the trick is not let our past become this chain tied to us. Always try to move on positively in life and believe me, things will change for the good. Forgive yourself, forgive your wife and move on.
BITS M 38 W 36 D 7 Married 15 yrs W left for 6 months in 2009 W Filed for D 01/03/11 piecing now...