I'll ask the OP a few questions:

1. What tyre width and pressure do you run?

2. How far below your saddle are your handlebars?

3. Just how long have you spent off the bike to try to recover?

I got a case of ischael bursitis last year, touring in Canada, on a new Brooks saddle on a new Ti bike, with tyre pressures somewhat higher than I normally run. It's take 12 months to subside enough to do rides over 50km, although I did do rides up to 300km in that year, and centuries a month up to April.

I've been resting a lot while in the US for the past month (driving instead of a lot of riding), and that appears to have helped heal the bursitis, although not entirely.

I am paying a lot more attention right now to rear tyre pressure after finding over the past couple of rides that lower is better -- I normally run my 25C tyres at 80psi, but have been up to 100psi on occasion, and that was what caused the problem in the first place.