If he is watching gay porn chances are that he is either bisexual or could be undercover or thinking about exploring. You need to understand that some people consider it to be okay being outside the box but will not call themselves gay or bisexuals even if they have tendencies to desire someone of the same gender. Unfortunately for you being with this person makes It alot harder because they are pretty much doing it in your presents and you are married and have a child. You should feel betrayed I dont blame you at all but you need to ask yourself was their any little things that you ignored in the beginning. Sometimes the writing is on the wall in front of us and we choose to ignore it . Do your research sit down and have an honest cconversation with him because you need to know and then you can decide what you Trulywant to do. Good luck to you.