I think that people stay with addict partners for many reasons.
Financial concerns, fear of living alone, hope that the partner will get sober and be the person they used to be, not wanting to be a single parent.
I will say what I most often say when this question is asked: unless the partner embraces recovery, things will only get worse. Alcohol makes us sick, and as we age, we get sicker.
Everyone is different. I have seen people who have no business being alive still walking around, but they are not healthy.
whether you stay or leave is no small decision and only you can make it, but, as others have said, you get one life.
How do you want to live it?
Final thought: No one on this site who has left their addict partner has ever said that they regretted it and wished they could undo it., at least not that I can remember.
If anything, they wished they had left sooner.
If you want a happy ending, that depends, of course, on where you stop your story.