Wow, sorry to hear about your injuries. It's really scary to get hurt and not even remember for sure what happened; you don't know what you need to be doing differently or whether it was just one of those things. But I have to say "Good for you" that you've taken lessons and explored your interests! I think each of us has to decide how much risk we're willing to take, and of course there are lots of things you can do to decrease the risks if you decide you're still passionate about riding.
As far as whether your injuries are worse than average, I think that's a question for your doctor or your trainer. From personal experience, I have had some broken bones in my early 40's and some bad falls (concussions, no breaks) in my 50's. The ones in my 50's slowed me down more than the earlier ones. I'm still active around horses, riding and driving. I am a LOT more careful since I am not as fearless as I was in my younger years, and the ground seems harder these days.
After a broken backbone in my late 30's, I took up driving (shorter fall to the ground if you have a wreck). The falls in my 50's were when I was getting back into trail riding, starting a green horse and was personally out of shape, out of balance, etc. So.....not a good match for me and my wise husband grounded me after a concussion, until I had a horse that was a better match for me. Today, my riding horse is shorter, calmer, stouter (easier for me to stay centered), 13 years old, very seasoned and not spooky. I took lessons, lost weight and try to stay in better shape, am very careful who I ride with, as I want them to be as careful and responsible as I am. If you think about driving defensively on your motorcycle I'm sure you'll realize that you do a lot of things to make yourself safer, although there's nothing you can do to guarantee your safety. It's the same with equestrian activities.
The choice of the horses you ride, riding style whether English versus Western (or Aussie - very hard to fall off an Aussie saddle!), the people you ride with, the safety of the environment for riding, your emergency skills for one rein stops and emergency dismount - all those factors may help you be safer. I completely understand your situation -- it's responsible of you to ask the questions and to be thinking of the impact on your family. Good luck - this isn't something that you have to decide right away...
Last edited by Ladytrails; 11-14-2010 at 08:39 PM.