Anyone for whom this story seriously hits home, but who has success stories to share?
I decided to start playing tennis, and it changed my life.
I had taken a few lesson when I was very young, and I played on my high school team, but it was not a very competitive or serious thing. I decided to dig my racquet out of the closet and give it a shot. Worst case scenario, I get some exercise.
As it turns out, my city has one of the largest, most active network of local tennis leagues in my state. There are hundreds of young (and old) people who play regularly. I signed up for a random team, and before I knew it, I was meeting 10-12 other guys for tennis practice and playing in league matches two to three times a week. I met some guys my age who were similar to me. We started getting better at tennis. The next year, I started my own team and a lot of the guys joined. Three years later, I've got a small network of about 20 guys I can comfortably call or text to meet up with to play tennis any time, and half of them are close enough with me to go out for a beer afterwards. Just last month, our team advanced to the state championship tournament, and it was a pretty awesome bonding experience to go on a road trip and stay for 3 nights.
I don't know what my life would be like if I didn't pick up tennis 3 years ago. I'm in better shape, I have more friends, and I am addicted to those endorphins I get every time I go out and play. I have to get my fix 3 times a week, at least.
If you're interested, google USTA and find out if there's a local league in your area.
Even if you are not athletic, give it a shot. There are a dozen different divisions, separated by ability level. Find a local tennis instructor and join a 'group lesson', where you and a handful of other beginners just hit balls and receive instruction from the coach. It's also very cheap, compared to golf or skiing or other sports mentioned in this thread. For starters, buy a $30 racquet and some decent $40 tennis shoes, and that's all you need.