Maternal grandmother - died in her early fifties from a brain haemorrhage (my mother is teetotal as a result)
aunt (daughter of the above) - ditto
cousin (son of the above) - went into multi-organ failure in his mid forties after years of heavy drinking and died, leaving a young family
cousin - sixties, divorced, two grown up kids who are estranged, not really functioning, pissing in a bag as he can barely walk. Was hospitalised for a internal bleed earlier this year and in hospital for months, not sure how he's still alive, it's no existence at all. Very intelligent man, had a good career, but if I had to guess I would say there was some undiagnosed neurodivergence, he drank as a crutch and got over dependent on it.
ex's mum - drank the best part of a bottle of vodka a night in front of the tv after her husband left her. No other interests at all, endlessly self pitying. Died in her fifties.
close friend - her father drank himself to death and she is doing her best to do the same. It's a shame as she's a wonderful person, but very damaged.
I'm in my fifties now, and have had/still have, several alcoholic friends. Some have been sober for many years, some have relapsed, some are 'functioning' alcoholics who don't think they have a problem, some are now (prematurely) dead as a direct result of their alcohol addiction.
Alcohol to me is the most insidious and dangerous of drugs. You cannot save him, he has to hit the bottom and make that decision himself.
You are doing the right thing in leaving, you must protect yourself and your child or it will destroy you too. I'm sorry you are in this position, please seek out support, and wish you all the best.