Why do I exercise and eat well and gain weight?

This seems helpful: http://exercise.about.com/od/weightloss/f/gainingweight.htm

...even if it says the same things they all say... but it does also add that if you are just starting an exercise program, it could take weeks or months to see any weight (fat) loss. And gaining muscle is normal and may even happen faster than fat loss. It seems better for me to not step on the scale, but it is disconcerting when I feel like I am getting stronger and healthier and then I pull out a pair of pants from a year or two ago and they don't even come close to buttoning or zipping. I feel like there is something wrong with me, like I have some sort of disease or something. But then I remember that over the summer while I was  walking the dog for 1-2 hours a day and hiking on weekends, I did get slimmer. I think I was also eating less, and definitely driving less. Keeping busy, I don't think I was as hungry. Then I came back, cut down on the exercise, started driving more, and was sad about being back in a less fun, less beautiful place. So many factors. And now it is January and I am working mostly at home and still doing a lot of driving.

And so, at this moment, I am trying to decide to do the new weight watchers for three months and just finally actually do it. Lose 30 lbs and finish the dissertation. That would be some treat and two really good ways to get on with my life that seems stalled in every way lately. When put that way it only makes sense. Until I look at my bank account and wonder if I will get my money's worth out of myself (can I dedicate myself to the online program or will it be a waste of my money?)? These questions always come back to me, what I am willing to do for myself, and what I am afraid of. Hmmm.