hi,
I really can't give advise but I can say your not alone. My husband of 14 years has done the same thing. I was angry at first. Felt betrayed! Then I set up the computer to track ever web page everyone went too. We each had our own profile so it was no mistake it was him. Then I took the evadence to him.
It did not help any really. He just got angry but he couldn't denie it. I'm not sure what to do now or if my steps were correct. I just don't let him touch me any more. Told him I feel durty because of the porn. Who is he thinking about while with me.
But we have other issues too. Far to many to go into here. I hope things get better for you both. Its a hard road to go down