mxz500rider, hope your friend has a full, quick recovery!
A few years back, I was with a few guys riding motorcycles, daytime ride, came through a 35 mph curve (with some gravel and landscape rock) and the 3rd guy in our group panicked, fixated on a 4x4 sign post and struck it, not good at all, internal injuries, broken wrist, helmet definately helped avoid a head injury & did it's job!
Luckily we were able call for help, got him airlifted and he survived-Thank God!
I know how you feel about not wanting to take part in a sport after something like what you experienced has happened.
I didn't know if I wanted to ride cycles after that incident, but after some time I was able to do it and enjoy it again. I may have become more aware when riding than before, and always keep it in mind that you need to be alert at all times, especially in remote areas!!