Honey, if you're being constantly compared with others, whether you know them or not; and if nothing you do is ever right and he always puts you down for it; and if you've caught him cheating at LEAST two times in this short period, I'd say that you have big problems. And it sounds to me like he's definitely not trying to keep this marriage together.
I don't blame you for wanting a divorce. If you don't want to TRY to keep this marriage together, then file for divorce.
If you WANT to try to keep it together, then ask him to go with you to marriage counseling. Then you could say that at least you tried.
Whatever you decide, I wish you the very best. God bless and please take care. Hugs, Lee