I have had TMJ related problems for 2 yrs: worst is muscle tightness around jaw which affects my ears. Could this last a lifetime. Do I need a splint?

Sleep & pain dentist. How your teeth & jaws come together can cause problems: adjustment of your teeth or orthodontics may be needed. Posture, esp. At work, can affect shoulder & neck problems affecting the jaw muscles & the ears (pain, stuffiness, hearing issues, balance). Sleep airway problems are associated with teeth grinding at night. This can also cause pain in the jaws. Medications & low ferritin: grinding.
SPLINT COULD HELP. This problem if TMJ related is treatable. A splint could be helpful.
Yes unless addressed. Whenever your jaw moves (in any direction) 3 of 4 muscles are engaged while one is inactive. Muscle pain and popping sounds indicate 1or 2 of those muscles 'firing' more strenuously than the 3rd. Chewing habits create a muscle memory, similar to a bodybuilder who can't straighten out his arms. Physical therapy is a good first step followed by a trip to the oral surgeon for eval. Splints will help.
Yes, Yes. Chronic problem. Recommend evaluation by a 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.