Re: I'm going completely insane here!!!
I don't believe you should contact him. But I know for sure that you shouldn't worry about how he is living his life while you are apart. It sounds like you have been problems for some time. Stand back and try to be objective. Some people thrive on hate, but I don't so I can't make suggestions from this angle so I will give them from another. Perhaps you can agree that the relationship wasn't working, and you could be concerned for his welfare. But, you shouldn't be hurt if he is looking elsewhere for happiness. Yes, you may have a lot of history together, I understand why you may want to hold onto that.
But, vicious cycles are created by re-creating the same relationship over and over. If you are unhappy with certain aspects of the relationship that you have shared, why keep re-creating it? Maybe it would be healthier for you both to move on. That doesn't mean that you need to be unconcerned about the other person; that person is obviously important to you. However, how about being interested in happiness for both of you, rather than upset that he may be happy without you. You could, afterall, find a relationship with somebody other than him, and be much happier yourself.
As I always say, you have to make the decision yourself. But, maybe this will help you come to the decision.