It is very understandable why you feel so bad.Do you have someone to talk to? A close friend or counselor even might help. It sounds like you are holding a lot of feelings inside, hence the stomach pain. I don't think the medication can cause stomach pain?
I tried Welbutrin, and just couldnt handle it at all. I was so dizzy I couldnt get thru the day,I had to leave work and come home and rest. It also made my tummy feel blah, kinda like I had to throw up but not quite.
Anyway, I got off that and my doc put me on celexa, and its helped me alot and I hadnt had any bad side effects.