I have chronic active epstein barr virus, migraines, tmj, bruxism, restless leg syndrome, etc. I am 5'5" & keep gaining wt. I am at 250lbs. Cause?

You may have . Sleep apnea issues. Have a sleep study done, and consult with your physician.
2 separate issues. and should be treated separately. 1.Ask your doctor about the weight loss options that best suit you and your individual situation. 2. See an OFP (Orofacial Pain specialist) for TMJ, bruxism, migraine and RLS.
Two consults . I would recommend a physical exam to rule out conditions associated with epstiein barr virus first. Then i would recommend a sleep test (polysomnogram, psg) in a sleep lab to test for obstructive sleep apnea (osa). Migraines, bruxism, and tmjoint disorders are commonly associated with osa. CPAP and oral appliances are used to treat osa.. Tmj/bruxism are best treated by oral appliances.
Ideal Weight 112-150. Weight change is due to a difference in the number of calories taken in (food) versus the number of calories expended (used in daily activity). In your case, you are eating more calories than you are using. In the us, the average person eats close to 3500 cal per day or more, but may only need 2000 calories, therefore the excess calories are stored as fat (weight gain). Talk to your doctor.
TMJ advice. Your regular MD should handle the non tMJ issues. For TMJ - complicated. See TMJ specialist. Any dentist can be a TMJ expert with the proper training and experience. Most commonly, oral surgeons, prosthodontists, and orofacial pain specialists. Ask your MD, your dentist and your dental society for referrals.