Your friend is addicted to gambling in such a way that he cannot get himself out of gambling addiction i.e. he can be said to be mentally disordered and he has placed gambling above all his activities. In this situation, no matter how much honest advice you give him, your advice will not be accepted by him and he will not act on your advice. But your friend is in a mistake because he has sold everything to recover his past losses and has gone gambling, in this case recovery of past losses is never possible no matter how much he gambles. In this case, your friend should refrain from all forms of gambling addiction and spend quality time with his family.