"purple heart" is fitting for a soldier.
It's surprising with the cornucopia of drugs today, there aren't more problems like yours... everyone's system is a bit different.
Some holistic things like nutritional supplements help repair nerve damage... again, not for everyone, but perhaps another stone to turn over...course, they cost $$ and times are tight as you say...
If I had arm strength issues, I do NOT think I'd want to be tree stand hunting, not even from a nice firm ladder--- seems it would still be risky getting up and down.
Hopefully, you have a pard to hunt with.
Keep the Faith, and prayers for healing!