I can relate to both the disability and the arthritis and a feeling of being useless.
But you're not, you know. People contribute in other ways to life other than working a 9-to-5. Sometimes, you don't even know what you do because you're going about your business and may not get feedback.
Hope they sort out your health issues. Spinal arthritis *sucks.* It really limits exercise.
Glad you're back.