I would recommend you read Allen Carr´s "Easy way to quit smoking". He explains why smokers believe that the cigarette eases stress, whilst this is just a phallacy.
If you are addicted to nicotine, about 20 minutes after the last cigarette your body starts craving. This craving causes discomfort, and stress. You start feeling anxious and focusing on getting the next shot of nicotine asap. This is stressful. Let´s say 50 degrees of stress.
If you are going through a difficult time you get stressed about it. Let´s say you are having financial problems. You receive a bill that you hadn´t accounted for, and your stress level soars. Let´s say this causes you a 100 degree stress level.
You have 150 degrees of stress.... you are desperate to feel better... you are a smoker, so the junkie way out is to smoke. Boom. You smoke and your stress decreases by 50 degrees (the stress caused by the lack of nicotine, by the addiction). But you are still stressed by 100 degrees due to the bill. You may feel that the cigarette has helped your stress, but it has only helped with the self-inflicted stress. Your real problem that stresses you is still there. You have achieved nothing.
It is like the man that wears shoes two sizes too small so that he can take them off every now and then and go "aaaaahhhhhh".
Non-smokers don´t add stress to their lives, and deal better with the normal stresses that life throws at them.
People that wear comfy shoes don´t spend the 24 hours of the day thinking about their feet.
Sorry about the long post. I also thought I smoked because I was a nervous person with a very stressful life. And realising that I was fooling myself was the first step to want to quit this awful addiction.
I wish you success this time. Please stay close to the board and let us know how you are doing.
:)