There's actually a lot you can do about what you did in the past.

1. Regret is different than (I'm sorry this sounds harsh) self-pity. Regret is a strong emotion that tells us, "Man, I messed up. I'm not doing that again!" So don't turn it around on yourself, use that to resolve to live better.

2. You need to correct what you've done. I would suggest apologizing sincerely in whatever way is appropriate. If you can approach those in your past, then that would be best. If I was one of those husbands though, I would suggest keeping your distance for safety sake so you might have to approach making amends with just yourself. They may or may not forgive you, but that's not up to you. The importance is that you are emotionally sorry for what you did.

3. Finally, learn how to forgive yourself. This is really difficult and a counselor can help you learn how to do this, but it is just as important as apologizing for what you did.