Hey just wanted to say you're brave in the fact your getting back on a horse after such an accident, I fell off a horse once too, past out woke up with the skin missing from my back still have a huge scar. But I found a really understanding instructor and now own a mare that has brought my back confidence and two years later I enjoy riding as much or more than ever.
I also use a tipperary riding vest, I don't remember the name of it, it is comfortable for me, but I spent lots of time trying on different ones figuring out sizing and which ones fit my shape, being flat chested helps too so super adjustable wasn't a problem.
Try a bunch if you can, and pick one you like.
Courage is being scared and saddling up any way (for get the quote's owner).