Sass can you not wear these water shoes? Or. Is it that the pool water aggravates your condition?
I have had to adapt my exercise to allow for weaknesses or build up certain muscle groups to protect. I know it isn't something everyone can do, though there are exercises adapted specially to accommodate a lot of specific limitations.
Certainly I feel better physically and mentally for being fitter. More able to fight anything coming my way! ( or better still, duck and weave!! )