I want my boyfriend to stop smoking weed
Why do you want him to stop smoking weed?
He doesn't pay as much attention to me as I'd like him to after he smokes.
I understand why you feel this way, but I don't think it's appropriate for you to ask your boyfriend to stop smoking weed if it's something he enjoys. If you want him to pay more attention to you then you should ask him to do that, not stop smoking.
I don't care. What I want is for him to stop smoking weed.
And if he refuses, what are you going to do? Are you going to leave him over weed?