Sounds like more underline emotional issues. He's obviously unhappy with his current life so he tries to compensate it with the thrill of high-stakes poker games, similar to how an addict abuses substances to mask the pain in their life.
If you can't convince him to stay away from casinos entirely and find other ways to bring joy into his life until hes financially stable and able to play poker for leisure... then he's going to have to learn it himself when he eventually loses his job too and is just straight homeless.
