I fell madly in love with someone and lost 100 pounds. Losing 100 pounds obviously changed my life and gave me a bunch of confidence. Eventually I had my heart broken by this woman and that sent me into a long and probably not healthy spout of dating.
Having the thing you love most in this world leave you and hurt you is the ultimate rejection-- after that nothing else really matters to you. I guess the benefit is that I had and have absolutely no fear of coming up to whomever I want at this point. Also, women seem to like men who have been in love; I think probably because it seems like sex isn't the only thing I'm looking for.
Anyways, after the breakup I dated like it was my job. I went through too many women to count. I thought moving on would fix things, but I eventually realized in order to move on I had to be okay with being single first. I ended up just hurting women that didn't deserve to be hurt. It's a pain that'll always be there, but I've learned to deal with it. It's made me stronger in the end. Also, I now have a great deal of knowledge on women and dating, so I'm here to give out some advice and hopefully help.
Here's a picture of my transformation for anyone who may be trying to improve their body/self image, maybe it can give you some inspiration.
http://img74.imageshack.us/img74/9645/55534062ud8.jpg
-Giovanni