When Chongo Chimp gets depressed he drinks heavily. This can result in several things...

More acute depression.

Dark humour, laced with biting sarcasm.

Hostile outbursts.

Morose withdrawal.

Lack of monetary funds.

Fistfights with strangers or ex-friends.

Getting arrested.

Getting evicted.

Hitting total absolute rock-bottom and sobering up.

Facing the truth: no one else is to blame.

Chongo has just enough wits that he usually manages to veer off the depressed track just soon enough to avoid complete disaster. He experiences a blinding flash of critical self-awareness, realizes that he's been acting like a complete idiot, and buckles down and gets to work on a new case. The work itself revitalizes him. This is the stuff that a private eye's life is made of, and it makes for good storylines too.

Chongo would probably tell your friend, "Stick a ripe mango in yer face and shut up, fer Chrissake!"