You think that smoking relaxes and chills you out.
But when you can't get through a day without a cigarette break, doesn't that stress you out too?! Change your habits and reflexes and try other ways of de-stressing: a cuppa and a chat with your (non-smoking) colleagues will relax you just as much as a cigarette.
Smoking doesn't actually relax you: nicotine is a stimulant. To relax properly and without ruining your health, use all the money you'll save on cigarettes to treat yourself to some relaxing massages or beauty treatments. You won't feel guilty about spending money on them, and they're much more effective than nicotine!