Injuries and lay off

Have any of you had to have an extended lay off from training? I weight-trained for 8 years (and before that was a swimmer) and stopped 2 years ago because of niggling injuries here and there and took up running.
Unfortunately after a year of running training I’ve got sciatica in my right leg from an old back injury from a fall, and have slightly torn my patellar tendon on on my right knee.
I haven’t ran in over a year and started weights again in Aug 2000 but have had had to stop because of a return of shoulder problems and my knee.
Sorry to rant on but it’s getting me down big time, after 10 weeks of complete rest I’ve wasted to 160lbs and 20% BF at 5 foot 9.
I’m really down to just walking everyday for exercise now, and it’s really messed my confidence up, weights and fitness being a very important part of my life.
I’m taking Glucosamine, and chondroitin at 3g a day plus I have a good physio who’s doing deep tissue massage to help with old scar tissue.I’m also about to see an orthopaedic surgeon re an MRI for my sciatica.
Again don’t want to bring down the forum with this but advice from people who’ve been there would be good.

If you can do any sorts of exercises, I would do them (even if it’s just grip training). Also, you might do some research into an EMS. It probably won’t pack any mass on you, but it could quite probably limit muscle loss. Maybe others will have some better advice. Good luck, and don’t let it get you down… getting through such things is a sign of a strength more important than that built in the gym.

find a good ART provider,and get into a core conditioning program.

Thanks for the replies.Unfortunately I live in England and there’re no ART prviders here.I’m going to consider travelling to US over summer in my summer break from university, if this is what’s needed.
What’s a core conditioning programme BTW?