hot chat with another girl is not a big deal???? OMG. I cannot beleive how this guy is doing mistake and acting like he is right...
Let me tell you onething...Chat become very common these days...friendship is okay. i do have chat friends..but it should not cross the limit.
I feel that you are not over reacting...tell him that he is cheating you. if he is not ready to listen to you, then he is not your Mr. right guy.
Shiva