He visited porn sites

So me and my boyfriend have been together since August and we live together etc.. He has had problems getting aroused since the beginning and says he really does not have much interest in sex, he says it has nothing to do with me but it's a problem he has had for about a year or so. He seems to enjoy it when we do have sex. I don't push the issue and just let him approach me when he wants sex. Today I received a alert from my wifi saying thet blocked a site on his phone called jerkmate that is a live porn/web cam site. It makes me wonder if he still has sexual interests/urges enough to go on those sites then it must be something with me. Also I am wondering what other sites he looks at and how often. My stomach of course dropped when I saw it. I don't plan on saying anything and just act like nothing is wrong but inside I am heartbroken.