I am not sure I completely understand your post. Are you giving him a year and a half to quit while you are in the USA?
I think a year and a half is definitely long enough to quit. But unfortunately often when people try to quit addictions for other people they can have relapses. It's really important that your bf finds reasons to quit for himself.
I would suggest if he is finding quitting difficult he try speaking to his doctor. Doctors can recommend all sorts of stuff now to help people quit smoking.
jess334 mentioned that its a bit difficult to understand your post completely and has provided excellent support above and using a GP to assist your BF with his smoking habit
Cigarettes are still (unfortunately) a legal product. You mentioned that your partner didnt smoke when you met him. Do you have any idea why he started smoking? I hope you can post back with any comments/questions you may have 🙂
my kind thoughts