Cheating and www.myspace.com

I am so very disgusted by people in general that cheat!!!! If your going to cheat and you want to play the field than why be in a relationship at all???? What....you want to have your cake and eat it too???? That isn't very good and it isn't a very honest thing to do...leading someone on, wasting their time. The story goes like this.....I have been dating someone exclusively (or at least I thought) for 4 years...come to find out after doing some investigating that he was flirting with other women online starting 6 months after we were together!!!!! He was on the Dilly, Face the Jury and myspace.com, just to name a few. I do some more digging and I see that he has been flirting and commenting on all of their pictures, telling them they are sexxxyyyy, hot, they have beautiful hair, eyes, legs, let's hook up, etc. on and on I see there are over 7000....yes over 7000 women he has on his myspace as friends...oh and he was giving out his phone number too and text messaging. I even got the chance to talk to one of the girls....the idiot sends her a picture of his penis....and he sent it to me too....at the same time....so I can see her number on the message and call her. Boy she told me some things I didn't know and suddenly all the pieces started coming together!!!!! He yelled at me after I confronted him with what I had found, he says he has done nothing wrong!!!! He called me names and told me I was psycho because I cant let it go!!! He lied to me, he wont admit to any of it even giving the girl his number....even after I spoke to the girl personally!!!!! He still lies and the girl told me personal things about myself that he told her about me too!!!!! I think he was wrong....any thoughts from you all out there???? Let me know what you think....am I really crazy like he says!!!!! Isn't the internet still considered to be cheating!!!!!!