>Not only am I filled with guilt, but I am filled with trepidation about losing my current girlfriend, who I actually hoped to get married to and start a family with. I know I was wrong for cheating and this might be my karma/punishment. Some might say that I deserve this to happen to me. Or that I don’t deserve a future with my current girlfriend.

You realize that every single one of these sentences, you are the only one that you're thinking about right?

And yes, she does deserve far better than you. For that matter so does the ex-girlfriend who didn't know that you were in a serious relationship when you slept with her again.

I'd say let these women find faithful and good partners and that you spend some time alone to work on yourself before you get involved with someone else and make their lives as messy as you just did to these two women.