Issues...help!

So me & my SO have been together 6 years, our sex life used to be awesome when we first started out (isn't it always?). But things from my past have kept my libido down these past 2 or so years...recently i caught him on craigslist ads and porn chat sites, seen actual conversations...and when confronted he says they were not actual people. Is that even a real thing?! And states that he has a sex problem. But wouldn't this have came up beforehand?! I understand everyone has needs and yes maybe i have been a little distant, but some of those feelings i cannot control. A touch or a the way he grabs me triggers memories and makes it damn near Impossible to bear having sex....any ideas to get out of this rutt?! Am i wrong for being hurt about the sites and conversations?!