Gambling is worth playing if you are aiming for entertainment and nothing more but if you are aiming for profits then its a different story hence its really impossible to make stable profits on gambling and you would always end up broke on the long run. In your situation convince your friend to stop gambling immediately before its too late.
Yes, Gambling is worth playing for those who have lots and lots of money but don't have a family or friends whom with they can spend time and money, but for those who have a family and have other ways to spend money and have all the entertainment, they should not even think of gambling at all. Playing gambling is not worth for them.