AITA for not liking my girlfriend smoking

Me (21) and my gf (20) have been together for 2 years now and recently I’ve noticed that on occasions she will have a puff of someone cigarette when out drinking. The first time she did it I told her I did not like it but she sad she only bum puffed it, but she just went out drinking with one of her friends the other night and afterward I saw pics she had taken on her phone of her smoking. I really do not like smoking and would prefer she didn’t do it but I really don’t want to act controlling and too in her face about it, but I have told her before that I don’t like it and it’s a huge deal breaker for me. Should I just leave it and see if she does it again?