Sometimes I can't forgive myself for my past cheating

Your dating it does not count.

Your not married.
You do not have children.
He nore you are not "tied the knot"
Your just fooling around and it was normal.

The better point is that he and his friend are still friends.

The biggest problem is that mentality. Oh we are "together" or Oh you shouldn't talk or associate with that person or whatever. Or oh I need to put the smack-down or get physical because they approach my woman.

You was dating it does not count. All you went to was a seminar for making you feel like a bottled up bug because he is over-protective and not trusting of you.

My advice is just to get married or make your relationship an open relationship. I feel sad that people are closed relationship mentality. Yeah AIDS/HIV/STDs no-thank you, or even "I am not the daddy-dance" mentality. Okay great.

The point being is that it is an over-stated mentality and sometimes you need to learn not to care. You see that even Burning-Man or some night-club parties, why you think people go to those things? Just to take pictures and buy drinks.

You are dating, not subjugated to somebodies power. People got paranoia's and the point being yes we all had when we were grade-schoolers and stupidity mentality of being wed-lock and married with children mentality.

You did nothing wrong and honestly it could happen again. He wants you to make you his, then what is there afterwards? What kind of life that would be?

I mean seriously I am not going to fight anymore. Girl wants me, and head-over-heels for me, and blah blah blah, I am not going to fight for her anymore like if she is a piece of meat, and I am the crazy-cave-man. I just realize hey that is life and is not love.

Again you and him are not married, you have no children, and even afterwards why not have an open-relationship? We might drop-dead, pass-out, and starve and all we cry about penises and vaginal areas. You have tribes in areas of the world that gets over that mentality and the faster the better.

What is this mosh you are typing? THEY ARE MARRIED, you twit. THEY HAVE CHILDREN, you twit. You are a complete and utter idiot and should not be dispensing your 'advice' to anyone.