djayr has some valid points.
Not to sound cruel or insensitive but his lifestyle choices lead me to believe you will outlive him.
Last year, my 52 year old neighbor dropped dead, autopsy report stated he had an enlarged heart, complication of many years of alcohol abuse. Another guy I knew, fell and bumped his head in an intoxicated state, he died instantly. And one of my daughter's friends mother, aspirated in her sleep, and died.
If it were me, I would be weighing all these odds, and would be very hesitant in paying him off.
SoaringSpirits, I am sure you will make the best decision for your situation, I have great empathy for what you are going through. Wishing you peace, joy, and love, you deserve it, my friend.