How do I find out if my boyfriend is a member/subscriber to any internet dating sites or sites?

My boyfriend left his email up on my computer one day, so I took a peek. I shouldn't have, because i saw old emails from dating websites. I was NOT a happy camper, to say the least. So, being psycho, I further investigated his emails and internet dating acounts and realized that he hadn't logged on or been active on the sites for a long time, approximately 1 month BEFORE we started dating. Who felt like an ? ME. Well, of course I got over feeling bad about it, and later tried to check up on him again via myspace. (I know I shouldnt have been doing all this, and I know Im psycho, but thats not the point). On myspace, some messages were exchanged between my boyfriend and some girl id never heard of before. I continued to read the rest of their conversation and immediately puked. I had never felt so hurt in my life. My boyfriend had apparently asked the girl if she ever wanted to **** to call him at his cell number. I totally flipped. I called my bf crying and vomiting wondering why he did that and that i couldnt be with him anymore. Well, later that afternoon, after numerous conversations with my bf to straighten this out, his best friend called me. The friend said that there was no way my bf would ever do that, and it had to have been a cruel joke by someone my bf knows. Then the friend made me go look at the girl's profile my bf had been chatting with, and thats when I realized that she was not cute at all, and was knocked up with her 2nd child at the age of 19, and (i hope i dont offend anyone) she had cerebal palsy and she looked deformed. I finally settled down, trusting the friend and my boyfriend who said he would never do that to me and he wouldnt have given me his myspace pword if he had something to hide. Well, months went by, and i found a virus on my computer. After further investigation of the 'cookies' on the computer, i found a screen name that was clearly my boyfriend's, and it was one i'd never seen before. Naturally, i 'investigated further', and found a thousand or so messages from sites on his email! i was mortified again, even though most of them were unread. HE HAD THE NERVE TO LOG ON TO THIS EMAIL ON MY COMPUTER! After a loooonnnngggg period of 'lindsey not trusting cory', I want to make sure he cleaned up his act like he said he would and start from scratch. How do I find out if he is on any internet dating sites, sites, or has alternate email addresses? please help..our 1 year anniversary is next month..Am I an idiot?