If you can't find my story I'll try to find it and boing it for you.
Low intensity running did not make the injury worse, rather the opposite. Forcing myself to keep moving with a proper running action was a vital part of the recovery process. Resting I found to be actually harmful.
It is unlikely that you will have the courage to massage yourself hard enough for the ideal treatment you need. This was certainly the case with the achilles, and also the extensor longus, for both of which I had regular deep tissue massages with my sports injury therapist. The pain was immense and at first took several days to recover from each time. I interspersed short runs between my visits, which also took several days to recover from at first. Massage starts with the muscles connected to the tendon (in my case the calf) before finishing off around the tendon itself. In the soft tissues all sorts of scar tissue builds up - "crystals" - which need breaking down and dispersing.
If the area is inflamed and swollen treatment is a very slow process but eventually you get there.
But bit by bit I improved but it did take 15 months altogether for the achilles tendonitis to clear up. Bad foot now as strong as the other one with not even a hint of trouble.
My Dr said AT "comes when it feels like it, and goes when it feels like it, regardless of what you do. You might as well resume your normal level of activity." I didn't like to tell him that my "normal level of activity" he might not regard normal!!