Swimming with health issues - share your stories?

Since most of us aren't teenagers any more, I'm pretty sure a large masters population is having to overcome all kinds of health issues on order to getin shape, and go as far as competing. I was starting to get pretty competetive 4-5 years ago and setting a lot of PB's, when in my mid to late 30's I got slammed with a lot of health issues, couple of which (ick) caused a lot of rapid heart rate even at rest, and made me very exercise intolerant. Some of this is getting under control, other things I just have to live with, and accept I can't push as hard as I used to :( I have a genetic blood disorder, thallasemia, which manifests itself in my case an untreatable chronic anemia, fast thyroid causing heartbeat irregularities (and other things), and one of arthritic conditions, scleroderma. In last couple years I'm just starting to figure out how to handle my newly dysfunctional body, and still keep active. It's been a very disheartening struggle, since at 40, I'm supposedly too young to be falling apart. Eh! I'd like to hear from people who are having to manage their health issues, so they can keep swimming, and even competing... I'm hoping this can be motivating to a *few* people.