My boyfriend is a smoker

My boyfriend, whom I love very much, is a smoker. At the beginning of our relationship, he had stopped and didn’t smoke for several months, but then he started again. Right now he tries to stop with patches, but it finds it really hard and he feels a lot of judgement and pressure from me.

It’s true that I don’t like it, but I also really want him to have the life he wants and I want our relationship to be free of this kind of tension.
Right now I think my model would be :

C: My boyfriend goes outside to smoke.
T: What a disgusting habit, he’s killing himself, why can’t he just stop.
E: Disgust, frustration.
A: I give him the cold shoulder.
R: Tension and disconnection in our relationship.

I have trouble building my intentional model, though. I even have trouble finding the emotion that I want to feel about this situation. I don’t wanna leave him just because of that, but I find the frustration really hard to bear. Do you have any advice about that?