Hey

I started in July 2004 and went from 200 lbs to 140 lbs by late Feb 2005 (so, about 7 months to lose 60 lbs). It took me another almost a YEAR to lose the last 13 lbs!
I plateaued at 1400-1600 calories from Feb - May 2005. In May, I really thought my body was done at 140. So, I increased my calories very slowly to about 1800-2000 (right around maintenance for someone of my age/weight/gender/height). By July I weighed 138. I was 135 by November 2005 and finally reached 127-128 around February 2006 (where I have been ever since).
I increased calories but I made up the caloric difference with additional healthy foods - added peanut butter, ate more Fage yogurt, etc. Everything else about my maintenance is exactly like losing weight (well, I don't enter calories exactly into Fitday anymore, it's more of a running mental estimate). I still plan meals, food journal, eat 5+ servings of vegetables, avoid fried foods, fast foods, soda, etc.
My own personal pet theory (not a doctor, dietician, nutritionist etc) is my body just got freaked out by a year's worth of low calories and decided to hang on to my fat reserves to protect me from starving. I really can't fault my body for doing what I would WANT it to do if I were really faced with a food shortage (which was the norm for most of human history and still is for many people around the globe). I started eating a little more (but apparently right under maintenance for me) and woosh, my body gave the "famine over - release the hips" command.
It is just my theory, I have no other explanation for why I lost the stubborn remaining weight eating more than I did initially in my weight loss journey. I have always been an accountable food journaler, so I know I was counting accurately during those times.
Congratulations on your amazing weight loss AND keeping it off for one year - keeping the weight off is a great victory! You might want to join us in the Maintainer's forum (there are often posters who are working on losing just a few lbs) or maybe you would find the Featherweights forum helpful.
You sound like you are on the right track with increased exercise - good luck!