Welcome. As the first poster, I claim the free drink.
It's morning, so I'm going to break some tradition and order up an Irish Car Bomb .
I've been in almost all of the places you are now. I've wished some pretty horrible things on someone. Know what? Betrayal or not, it does nothing for you. It doesn't change anything. It doesn't make you feel any better. And THAT, my friend is what you need. To make YOU feel better. I'll throw out some of the mistakes I made early on that didn't make me feel better.
Catering to the ex, even through the divorce. Getting into a new relationship waaaaay too early (that one ended quickly). Thinking too little about what I need and want for myself.
We all came here initially to save our marriages. The best thing any of us can come away from here with, married or not, is saving ourselves.
So, my suggestion is really take a long hard look at what it takes to let some of that anger go. Yup, you were betrayed. Join the club. We've got jackets, as Shrek said. Holding resentment and anger and all that for events that are past is giving control over your emotions to the people who did this to you. Is that what you want?
That's just my $.02.
And welcome over to the Surviving forum. This is a great, great, great group of people who can teach everyone a lot about life.