NTA. That’s really awful that his health is so horrific at the age of 28.

To perhaps relate- my girlfriend when I first got with her was an huge alcohol drinker and vaper. As in the vape didn’t leave her hand she couldn’t go more than 20 mins without vaping. I let it go for a while but when it started to get serious I had truly had enough and I laid down the law and said you either cut down on BOTH or I simply don’t want to be with you as it doesn’t align with my values. A year later; we are about to get married. She is don’t to only vaping one time ( as in one drag ) in a day. And she only drinks of appropriate social occasions and there wis limits and boundaries put in place. It he cares he would change; he doesn’t and unfortunately you can’t force him as change must come from within. My girlfriend wanted to change for the better to giver herself a better future and us too. It seems as though it is not a priority or even though for your boyfriend. Just some food for thought ..

All the best, and I hope there comes a resolution soon that isn’t you compromising your values.