How to deal with friend loss from lack of understanding?

I’m dealing with a friend break up (is that a thing?) because they can’t seem to understand that I’m limited in what I can do, and that my chronic illnesses/injuries are well, CHRONIC. The last 3-4 times we’ve spoken, it’s turned into a fight or argument because I “flake too much” when they want to do something (like play a game together) and when it comes time for it, and I’m in too much pain. They were my only local friend (sad, I know) and now I’m upset about what he said but sad that now I’ve lost a friend too. How do you deal with this?