I lost loads of weight when I got married by doing Atkins but put it all back on and more.
This week I bought a pair of size 12 (UK) jeans and I am now dedicated to getting into them whatever it takes. I've never been slim, and I am envious of everyone who is!
Losing weight is the one single thing that will improve my life and I plan to do it this year.
It sounds like you've already got the right mindset!
I'm sure you can find somewhere you feel right at home around here. There are forums for almost every popular diet imaginable, and the same goes for exercise programs.