I just wanted to let you know that I understand what it's like to be young with a serious injury.
I was a cross-country runner in high school; I had a full ride scholarship to a Division I school for softball. And then I essentially crushed my foot my senior year. It's devastating to be told as a teenager that you aren't as young and vital as you're supposed to be. My injury put me into a great deal of depression and denial that lasted through my early-mid 20s. I did a lot of stupid things that caused greater injury to myself, and I could have had normal functioning a couple years ago.
I've had to have several reconstructive surgeries on it. I had to walk with cane for several years. In the couple years, they've developed some new equipment and now I have a fully functional partly metal/plastic/bionic woman foot.
11 years ago, they told me I would never walk without pain and have to use some sort of assistance device. After surgery last spring, I don't even have a limp.
Medical technology does advance drastically, and there is always hope in advances. Don't let it get you down.
For exercise, every situation is different. Always, always, always consult with your doctor and PT for what's a activity for you. For me, I thought swimming would be an ideal activity (not load bearing), but the foot positioning in swimming could have done drastic damage to some fragile connections (at the time). I have spent more time on a rowing machine in the past 11 years than I ever imagined was possible. ;>
So talk through with your health care providers. Be proactive with it. I know it's hard to get into the "take it in stride" and "okay, so what's next" mentality, but once I've gotten to that place...man, I've been unstoppable.
You're also more than welcome to message me anytime if you need someone to talk to about it. A big port in working through it is support.