How do I stop smoking?

I am not addicted to smoking but I smoke 1 cigarette a day. It was 1 cigarettes a month when I started. Then it became 2 in a month, 3 in a month, 2 in a week, 5 in a week and finally everyday. Last week I smoked 7 cigarettes. If I get so angry or very stressed, I smoke 2 cigarettes a day but its not a thing that happens so often. My boyfriend is a smoker too. He smokes about 40 cigarettes a week. And his cigarette has nicotine and the other harmful things more than mine. I started smoking in august, as I remember he started about 7-8 months ago. When we smoke together, its good. But actually I dont want to smoke anymore because I dont want to need it. I used to live without it and now I can live without it again. But its really hard when he doesnt want to stop smoking. When he smokes next to me, I want to smoke too. If I stop smoking, I would start again. Or even I stop myself about not to start again, when he kisses me, his lips taste like cigarette. It felt disgusting at the beginning but now I dont feel a negative thing about how his lips taste like because mine are the same now. If I stop smoking, I can feel disgusted again. I feel really confused. If I stop smoking, I am going to do it in new year party on 31st december. I am going to smoke my last cigarettes. Or I will never stop I guess… Comments please? I really need your help. There’s nobody that I can trust and talk with about this subject.