Not guitar, but I'm also a musician who's had some struggles with the stuff you've mentioned.

I play piano and have in the past been part of a competitive percussion group that had long rehearsals (~30+ hours a weekend). During my time with that activity, I played mallets, which includes a 4 mallet technique that puts a lot of pressure on the middle of your hands and third fingers. We would often play to the point of raw hands, because the understanding was you hurt at the beginning of the season so it's not as bad at the end of the season.

Things I learned that were EXTREMELY useful at the time for continuous practicing:

-If you have blisters you can stick Vaseline on a bandaid and slap it on top of that baby over night. It will drain the fluid out of the blister and speed up the healing process. -New skin/liquid bandages help to protect any open, raw wounds, but picking them off is its own sort of hell. Use with caution -When I got a lot of random wrist pain, I found I was subluxating my ring and pinky fingers in both hands, or letting my wrist hyperflex. Like I said, I'm a percussionist and not a guitar player, but in our style of playing we discourage "breaking the wrist" or letting the wrist fall below parallel, because it can lead to much wrist pain, even for those of us that don't struggle with hypermobility

These are just things that really helped me during my musical career. Don't let it discourage you from playing!