I can empathize like crazy. Right after Thanksgiving I realized I was heavier than I had ever been and I ever thought I'd be, and feeling pretty awful physically. I knew my weight had been creeping up over the course of the summer and fall and I'd made an effort to exercise more, but didn't make any progress.
When I was younger, I didn't really have to change much about the way I ate to lose weight, I'd just increase my activity. As I've gotten older obviously my metabolism has changed and I needed to be sort of re-taught how to eat, I guess.
I ended up joining Weight Watchers Online (no meetings) and I've been really happy with it and really have nothing bad to say about it. It's not that expensive (~$20/month), it's super easy, and there's no reason you can't make the other changes to your diet you're considering because you're not limited to specific foods. Even if you only do it for a month or two, I've found that it has really helped me "reset" my perspective on stuff like portion size and making better food choices. I've lost about 12# so far. FWIW, YMMV, etc.