I'm a shortie, only 5'2", and have always struggled with my weight. I've yo-yo'd more times than I can tell you, I must have lost 100's of pounds, it's just the same 10-20 pounds over and over ... When I hit 40, I successfully lost weight and actually maintained in the 120's for several years. I was exercising regularly, even ran/walked a marathon! But, I allowed work pressures and a busy life to crowd out my exercise program and unhealthy eating patterns to re-establish. While I lived in Denial Land, all of the weight - and more - crept back on over a couple of years.
Finally, in Jan of last year, I hit the wall. I was outgrowing even my "fat" clothes and I refused to buy yet a bigger size. When I finally got on the scale to confront reality, I was 150 pounds, more than I ever weighed in my life, even when 9 months pregnant! That was It.
I started exercising regularly again. I didn't follow any particular "diet", just emphasized vegetables/fruits/salad and lean proteins, and limited fats, carbs and sweets. My initial goal was 125, but when I got there, I thought, why not try for 115? My "ideal weight" in my head has always been 110, so if I can get to between 110 and 115, that would be perfect. It took me all year, but by December, I had reached 115! I am currently at 113, and am working to stay within that 110-115 pound window. So far, I've maintained for 3 months!
I feel that I'm in the best shape of my life (I'm 48). I'm running again, and am faster than I used to be because I'm lighter! I feel stronger, and I'm back into a size 4P or XS, the size I was before I had children.
Measurements: 33 / 26 / 34.5I'm proof that you're never too old to work to improve yourself, and you can regain at least something close to the body you had when you were younger. OK, it's a little more wrinkly and saggy, but not bad for an old lady!
I've resolved that this time will be different, this time I WILL keep it off. This is a permanent lifestyle change. The keys for me are the consistent exercise program, monitoring my weight regularly, and keeping close tabs on daily food intake. I recently started keeping a food diary, so that I can dial in on the number of calories I can eat and still maintain. Thanks for this forum, it helps to get all of those hints, tips and recipes!
Congrats on your loss and 3 months maintenance!!! Please join us on the weekly chat thread, we're always glad to have new people!
MBN! And 
for being in the best shape of your life at 48!!