RPE and intensity question // frequent injuries

I’ve always made amazing progress on these templates, but then I run into an injury (shoulder pain that’s pretty severe, hip pain, back pin, etc. ( About 5 pounds every week or every other week across most of my lifts until I get a flare up usually every 6 or so weeks)

i am wondering if I’m misunderstanding how to measure RPE. An RPE 9 in my understanding is a weight I could grind out for another rep. It feels incredibly heavy to me. An RPE 8 feels quite heavy, but not without it still moving relatively quick.

The RPE 9 and 8s so frequently I think are just too much for me currently. What do you guys think, though?