De-Lurking

Hi everyone, my name is John and after lurking around the forums for over a month I figured I might as well introduce myself because I seem to be sticking to this thing
I will not burden you with my life story, but a little background: I joined the Army when I was 17 in 2002. I had put on a lot of weight from 15-17 but I really wanted to join the Army. So I went on strict diet and did some light exercising. I dropped from 235 down to 195 and was allowed to enlist. In Basic Training I dropped down to 172 but upon graduation I was at 179. Then during the next 7 years my weight was roughly 182-192, although this BMI is considered overweight for my height, I looked either normal, or after a year plus of hitting the weights, very fit.
But then in 2009 I returned from my last tour to Iraq and started transitioning out of the Army (ETS'd in April 2010), it felt so great not to have to worry about physical fitness or weight anymore! I sort of went crazy. I also got engaged and quit smoking in the beginning of 2010 (smoked for 7 years and I never will again, because it was so damn hard to quit!). Needless to say my weight skyrocketed. I dreaded the scale and avoided it until one day I finally worked up the courage to look and holy bovines! 250 lbs! I had NEVER weighed that much in my life!
I immediately cut out all fast food and soda pops, started walking more and my weight dropped fast down to 220. This was my new 'normal' until recently. (was back up to 230.0 lbs by the time I signed up for MFP)
My whole life I have never had any problems losing weight whenever I decided to, until recently. After my fiance and I broke up (not related to weight at all) I would go through bouts of depression which I treated with food, that in combination with old Army knee injuries (aggravated by weight gain) made it extremely hard for me to lose weight. Every time I tried, I would plan some extreme workout schedules that I could have done in the Army, but since I was so out of shape all I managed to do was injure myself a couple times.
Mid-June this year a friend of mine and I made a bet to see who could lose the most weight by the weekend before college classes start (Sept. 11th). So I dusted off my bicycle that I hadn't ridden in 5 or more years and downloaded the MFP mobile app. I didn't really get serious though at first, using summer school as an excuse to put off losing weight, until a few weeks later I got talked into going on a 4 mile run with some friends of mine from college. Although they were all a lot younger then me, the fact that I was just about the slowest person in what 2 years ago I would have considered an EASY run and finished 1st no problem, but instead found myself huffing and puffing and doing a lot of walking, was very frustrating.
That was it. Time to get Serious.
I started riding my bike 5 days a week (sometimes less, I always take the weekends off) because it is low impact which is good for my bad knees, and a lot more enjoyable for me then running! I decided not to focus on time or distance, instead I set my watch timer for 30 minutes and ride down a local bike path until the alarm sounds, then I turn around and head back. I also consume about 1.6k calories a day, I have read a lot on here that you should eat your exercise calories so I am going to test that out a little this week by bumping it up to 2,000 calories, not quite what I burn but enough to see if there is a difference.
That was a month ago and I've lost 21 lbs since then (or 1.5 stone). I've decided to treat this like how I treated quitting smoking, putting attitude ahead of everything else. The only way I was able to quit smoking after years of struggling was to join an online support group and educate myself, so this seems like a good start.
I will probably still mostly lurk, but I will post major milestones and read a lot .