Losing weight….?

I am trying to lose weight however there is a catch I am in a wheelchair 95% of the time due to injuries to my back, ankles, knees, & my hip. I recently was told by my Orthopedic Surgeon I have arthritis in both of my feet, knees, & hips. I would like to lose 50 pounds by Sept for a wedding & photo’s with my hubby. Also, I am sick of looking like the Pillsbury Dough Boy. I suffer from hypoglycemia, chronic bronchitis, asthma, I have had a hysterectomy from cysts & endometriosis, & I also have brain damage from a head injury (car accident) which placed me in this wheelchair. Does anyone have any suggestions? The doctors suggestion hasn’t worked in the last year & that is watching my calorie intake. I take in no more than 1200 calories per day. My family bought me a diet program called Calorie King Nutrition when the doctor placed me on the diet last year the only exercise I get is at Physical Therapy. So does anyone have any suggestions????