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.
Mental disorders are one of the risks that can occur if they are addicted to gambling, especially if they themselves cannot stop even though they have experienced many losses. with the many defeats they experience, it will make them experience pressure that can affect their own mental health which ends in mental disorders, apart from that, they become addicted, this is because their thinking has been influenced by gambling, so mental disorders are a definite impact. It happens, some are even still aware of the pressure they are experiencing but because they are unable to bear the pressure they end their lives, it's scary.
Indeed, even those who are addicted will not easily be able to accept advice from other people, even from their own family members. If they are addicted to thinking, they will not think about other things, it is unlikely that they will be able to think about other things around them. because if they are addicted to gambling, they will only focus on what they want and gambling is what they want, so they will continue to gamble even though they have experienced many losses and losses, even with bad consequences.