It’s strange, isn’t it? You want to stop smoking, but each time you see all your friends or colleagues smoking and having a good time, you feel that you can’t quite enjoy the fun unless you’re smoking too. You’re reminded of how great it felt back then before you quit. This is part of what I call romancing the cigarette. There is no good reason for this, other than your psyche making an association between the two: having fun and having a cigarette.
Think for a moment how a non-smoker feels when having fun with friends who smoke. They probably feel much the same joy as you, except that the smoking part doesn’t even register. It’s irrelevant. There is no connection between having fun and smoking, other than inside your mind.