Hi, all!
I'm a little late to this party, but the title caught my eye.
My story is similar to sadscoop's, in that I yo-yo'd for years -- I had my skinny, fit years, and then I had my "blimp" years. 
I was a runner and a dedicated exerciser until I met my X. He was a devoted non-exerciser and over time, his bad habits rubbed off on me.
We were together for almost 14 years, and it seemed that I added about 5 lbs. per year, helped along by the fact that I had to take prednisone for about 5 years for my asthma (now managed with Advair -- my godsend!!) When I couldn't breathe, I couldn't exercise, and the weight just seemed to pile on by itself.
Last April was D-Day for me, and within about a 2-month time span, I lost about 40 lbs., and have since lost another 15. At one point during my relationship, I hit 172. I'm only 5'5", so I was wearing a size 16 and climbing! Now, I fluctuate between 110-115, and I let the fit of my clothes tell me how I'm doing.
A couple of things were key for me. I signed up with Team in Training, a group that raises money for the Leukemia and Lymphoma Society, by training people to run or walk marathons/half-marathons or triathlons. At first, I signed up just to have a reason to get up in the morning, as my X moved on and in with OW. I thought that at some point during the training that I would drop out, but what a surprise!! The more I kept up with the group training sessions, the more passionate I became about the cause and the workouts. I also developed friendships with others and gained such a sense of purpose from raising money for such a worthwhile cause.
Long story longer, I went on to complete my very first marathon last October, and ran a half-marathon in December, dressed as Elvis, but that's another story!!
I'm training for ANOTHER marathon in March, and have committed to 2 others during 2008. My body has taken on a whole new shape, although all the exercise in the world won't cure the excess skin that was created from those years of excess and neglect. 
I guess at some point I'll have to start a *nip and tuck* thread to talk about how I solved that problem! 
I don't even follow a points plan now, although I still remember it well from my WW days. I mostly eat fresh veggies, fruits, tons of Boca Burgers, Gardenburger riblets, buffalo wings (vegetarian) and lots of Weight Watchers and Lean Cuisine entrees. Just this week, my market had Lean Cuisine dinners and pizzas @ 6 for $10. I stocked up big time!! I also buy lots of yogurt -- nonfat and lowfat Dannon. Those little containers make great, guilt-free snacks.
I also drink buckets of coffee everyday. Believe it or not, research has shown that coffee is great prior to exercise! It works for me.
One of the things I learned in training was that it's better to eat AFTER exercise, as your body's metabolism is working at its peak for about an hour after vigorous exercise and will be more efficient at burning calories. So, go run, do your treadmill, a fast walk or whatever -- then, go eat!!
Also, if you're not eating pre-packaged food, it's really easy to be careless with portion sizes. That alone is a diet killer. A rule of thumb is to keep portion sizes to the size of your fist. Comes in handy if you're eating out and wondering how much of something you should eat.
If you have El Pollo Loco in your area, this place is a fast-food godsend!! All sorts of foods on their menu that are healthy and diet-friendly. They also post a nutrition list, stating calories of each item, as well as fat grams, if you're keeping score. Many days, I've hit the drive-thru, ordering different veggies, salads, beans and I'm always full when I'm finished.
If you eat at Taco Bell, the bean burrito is another good choice.
Words to look for when ordering are *baked, steamed, broiled,boiled, grilled*. Items to avoid like the plague are *breaded, fried, deep-fried*.
Just in case any of you are thinking that you can't do this, let me tell you that I am in my 50s and am wearing a smaller size now than when I was in high school. My X's cheating may have kick-started my weight loss, but I have taken the ball and literally run with it, You can, too!!
Keep up the great work, everyone. You can do this. WE can do this!! We are strong. We are beautiful. We are invincible!! (Oh God, now I sound like that Helen Reddy song. 
I'll stop now. 
)
