Jillygirl posted this a while ago, it just may answer some of your questions
Depression is an issue of focus for many who quit smoking. At times, quitting smoking is an extremely difficult thing to do, and it is difficult enough when you're feeling happy. I would venture to guess that many people have relapsed during periods of depression; it is more difficult to stay focused and maintain resolve and motivation. For those people who suffer bouts of depression during the cessation process, the condition is usually mild and temporary.
People who have been diagnosed and or treated for depression prior to quitting smoking should monitor any changes in symptoms carefully as they begin and move forward in their smoke-free journey. Some may experience changes in their symptoms, which may necessitate a change in treatment. If you experience drastic mood changes when you quit smoking, or if they persist for an extended period of time, a visit with your physician is advisable.
If you find yourself suffering the more common temporary emotional upset, try to relax and let the feelings come as they will. Quitting is a big change in lifestyle, and you will react, to some degree, both emotionally and physically. And think about it; there really is no reason to deny your emotions; they are personal, and they belong to you.
Symptoms of depression may include:
sleeplessness
sadness
difficulty concentrating
anxiety or an "empty feeling
fatigue
changes in appetite (more or less)
loss of interest in hobbies, activities
emotional irritability
While quitting smoking, the body and the mind are in a state of transition, and it's not uncommon for new ex-smokers to struggle with their emotions.
Gratitude
It helps to build up a reservoir of gratitude. When you're feeling down and having a difficult time finding the positives, quitting smoking is always there; you can always feel good about that. Take time at the end of the day to acknowledge the importance of what you are working to accomplish. It will help you fill that reservoir. Find comfort in knowing that you are being kind to your body. Gratitude will help offset negative feelings and make it easier for you to manage depression due to quitting tobacco.
Change Your Mind
One of the greatest challenges new ex-smokers face is a very important change in perspective. It is that shift in thinking from seeing smoking as an exercise in deprivation to realizing that it is in fact one of the best gifts you've ever given to yourself. This is a crucial step in the process, and it is with this transformation that many see the symptoms of depression begin to lift.
While you are moving through this transitional period, crying, whining, and even screaming are all preferable to inhaling deadly chemicals. Early in the quitting process, some resort to lighting up because they perceive smoking to be something that offers comfort.
Smoking is not comforting; it is familiar.
Time away from smoking makes it less familiar; you'll begin to see nicotine for what it is...a highly addictive drug which robs people of time with those they love and seeks to kill, one puff at a time...if you let it. Give yourself time to develop new and healthier coping strategies. Don't buy the lie. There is never a good reason to light up.
It's likely that many of you who are feeling down, felt happy recently. You'll feel that way again. In the meantime, you can find comfort in turning to your friends, your family, or your faith. In time, these will become the more familiar sources of comfort to you, and smoking will become that thing that you thought used to make you feel better. Take comfort too, in knowing that millions of people have been through this process and not only have they lived to tell about it, but many include it among the most rewarding and life-affirming experiences of their lives.
So, if you've quit smoking in the last few weeks or months and are feeling blue, please be patient with yourself. You are going through some big changes, and your body and mind need some time to adjust. Do any little things you can think of to give yourself a little lift. Rent a comedy, try a new hairstyle, call a friend, go shopping; spend a little of the money you're saving since you quit, and buy yourself something special. Keep reminding yourself that it is a temporary state, and you'll find happier days ahead; with them will come a tremendous sense of pride and empowerment.