Hi and welcome:-) It sounds like mentally you are setting yourself up to fail by all the hurdles you list. If you think it will be difficult, it will be. I don't find it any harder to cook Primal than I did vegetarian. I have a lot of pain in my body, but I play and exercise anyway. I find for me it usually helps. If I don't exercise or breathe fresh air, I get really depressed.
Good luck to you and I hope you can find a way to embrace it if you are going to do it instead of setting it up in your mind to be a sacrifice and giant undertaking. I also hope if you do it, that you start feeling better! I understand what it feels like to be young yet your body feel ancient.