"just give it a rest, will you ?"
psychologically, you refuse to be slowed or stopped by your injuries, you force yourself to continue.
Perhaps your mind/body is/are rebelling ?
This is the voice of bitter experience speaking. I've had a few really bad injuries over the years, especially my lower back which I've hurt 3 times, and a bad dose of plantar fasciitis. I tried to struggle on through the pain like you are, but eventually stopped everything for 8 weeks each time to let my body heal. It's a tough decision to make but it may be worth it in the long run.
If you can find another activity to help keep you fit then do it as long as you don't feel any pain or discomfort during or afterwards, and try and do any strengthening exercises recommended by a good physio who knows about running.
The "do what you can" is the recommendation of the osteopath, and basically everyone writing about sciatica (slow, painful recovery). It's not like a proper running injury which you can aggravate by training. The breathlessness I don't understand, maybe that is the mind just giving up. Maybe I'll rest up next week (oh wait, Jane wants to go on a cycling holiday...)