To be honest, if you were unfaithful.. what would you expect form her.. she may not act like she has no clue but believe me instict does play a part..
if you felt better with another women than there is a problem right then and there... it proves you are not ment to be..
and her being with another guy might have started as a shoulder to cry on.. and possibly this guy is making her feel better.. but there again that proves it was not ment to be..
my question is.. why stay when others make you feel better about yourself?
thats just my opinion
