Benefits of smoking cigarettes?

My girlfriend has threatened to break up with me several times now unless I cut down to a pack a week. I'm not addicted but it does help me get through my day. I keep trying to tell her that but she doesn't believe me and keeps saying that it's actually bad. I want to prove to my girlfriend that smoking cigarettes is actually good for you so that she can stop judging me over it but I can't find any info online to back that up. Can anyone help me find some resources that list the health benefits of cigarettes? Like how nicotine kills germs or anything like that?