This is difficult.
Al-Anon is a good suggestion.
You really can't do anything for an addict until s/he finally decides on their own to stop. From what I can tell, there is little you can do other than emotionally support him when he does try to make an attempt (like rehab) to quit.
Giving him money or helping him when he's not getting clean probably only helps him support his addiction (as you found out before).
It's hard with someone you love. Just let him know you do love him and will be there for him when he does stop.