I've posted for a while occasionally but I don't think I've introduced myself.
24 years old (going on 25), was 155-160lbs at 19-20 years old and decided to make the change. Not sure what lead to it - I think it was having to buy pants in a size 12 that shocked me. I was probably 90lbs in high school (metabolism - my dad is a rail, my mom is the average 50yr old woman who has had kids!).
So I eventually went down to 120lbs after a year, then down to 110-112lbs last year (I was training for a fitness exam, doing tons of working out, and was in the best shape of my life BUT I was too thin to do the strength training I really wanted), so now I am at 118lbs and have maintained that for a year.
I eat a very healthy diet BUT I also make room for treats. I don't care about sugar foods so that helps me. I love salty/spicy - salt and vinegar potato chips are my favourite. My BF is very athletic and is trying to lose weight himself so he is very cooperative and encouraging when it comes to fitness.
My closest friend and my sister are both overweight, neither of them are ready to do anything about it, but I hope one day they will "have enough" and I will be more than ready to give advice. Until then - I will just try and model a healthy lifestyle.