How can I help my parents recover from a bankruptcy and now gambling addiction?

Be Careful. Your wanting to help is admirable. However, be carefule to not become a primary enabler. It might be possible that the bankruptcy was caused by a gambling addiction. You can suggest counseling for the addiction, a secured credit card to help them rebuild credit slowly, suggest they keep a close eye on their credit score, etc. Do not loan them money! remember, you are the child.
Detach. Be supportive without any agenda of your own. Be neutral and maintain healthy boundaries.