Is it a matter of forgiving over the porn? He's not taken responsibility for it, which to me tells me that he's not sorry. He's been going behind your back for two years, that tells me his attitude to porn. People have different levels of tolerance to porn, and it sounds like you both will never agree on this subject. If it's something he truly seems as harmless fun, he will never understand how it upsets you.

Lying over the strippers is awful and should be sorted out but it may be a case where neither of you will ever get the other to see each others viewpoint, so it may be one of those situations where nothing moves on, and you just keep getting lied to. Only you can decide if you accept him for what he is so he doesn't lie, or find someone who shares the same values as you, or is mature enough to put you first if this situation ever arises again.

I am sorry that you've been hurt, and I hope you do whatever is right for you.

Hugs.