Chantix, side effects and weight gain!

Hi all,We need some help!! I have been lurking on here for several months now and think this is a great place for support. My girlfriend just quit smoking 2 weeks ago! Some of you might remember my posts back last summer about getting her to quit. Well she finally decided she wanted to try it as she knew 3 packs a day was not doing her any good. She talked to her doc and got on the Chantix during the holidays. Since she was such a heavy smoker,smoking cessation, she thought it would be a good idea to also try Hypnosis if the drug did not work too well for her. Well she was not able to quit completely and at week 5 on the meds was still smoking between 8 and 20 a day (was 3 packs a day before so the drug was working!) She finally decided to try the hypnosis and was able to quit on the spot!!!!! Has been 2 weeks now and it is getting better by the day! BUT! There have been severe side effects. Mood swings, irritibility, depression, water retention,quit smoking, bloating and Weight gain. Well this last one is throwing her over the edge. She has gained almost 20 lbs in 6 weeks. She has been snacking more than normal and we understand that smoking sapresses the appitite and also burns calories (from over working the heart by increasing the heart rate and increasing the blood sugar levels fooling the body into thinking it is full) So we figured 600 calories a day is what she used to burn. (200 calories per pack) She did slack off on the excercising the first month or so but she is now working out 1 hour a day. She is watching what she eats but has severe hunger pains and finds herself snacking all the time. So this increase in calories and the snacking is clearly causing her to gain weight. But it seems to be half a lbs or 1lbs a day! She is really upset! Is this normal? What can she do to stop this weight gain and start loosing? With a reduction of burning 600 calories right off the top, how can she beat this???We really want her to get off the meds asap but it's only been 2 months and only 2 weeks smoke free. She could easily relapse as it is too soon. But also the side affects are real bad. She has been so angry, irritable and rageful! We have had some pretty bad fights. I am trying to be as supportive as I can, but there is only so much I can do. Maybe someone can shed some light on what we can do! Any ideas would be greatly appreciated!!!!