Brother CF4, you are in a very difficult situation. From another perspective, however, you must understand that once you did something wrong, you have to suffer the consequence. That's why nowadays people are all talking about acting proactively (do not gamble in your case) as it is too late for sure after all these had happened.
So in my humble opinion, what you can do (and expect now) is to give your best shot to win back the trust of your wife. Stop gambling is only just the beginning. The more important and unfortunately the really tough part is how do you settle your loans as a result of all those years when you gamble like crazy. There are other practical problem that other people simply can't give you any advice or help, and it is up to you and your wife to face them alone.
So don't think too much, but act. Leave the rest to your destiny and hope for the best. In the end if you wife leave you, you have already done your best, and you are merely paying back for what you did to her.