Feeling Sooo Lost And Confused

I was in a marriage at a very young age and 6 months later I caught my spouse with another woman. Needless to say i ended my marriage.I have now been in a relationship for the past 13 yrs and next year we were planning on getting married, I truly beleived he was the 1 and only for me. For the past 6 months I have recently found out he has been searching out websites like match.com he has been getting emails with strings attached that I can't open and he's somehow created a link through fb where he comes through as one of my friends.I have confronted him and he claims he never goes to theese sites Ive even showed him the stuff i've found and he claims that it's a scam. I don't beleive he's had an affair yet but I truly believe going to theese sites are just the beginning of whats to come. I've been sooo depressed and have lost 15 pounds in the last 3 weeks. Don't think I will ever end up with anyone ever again!