50 is not old enough to have “done your job”. Your daughter doesn’t need you around? You say she is a junior in High School, so she is 16 years old, maybe 17?
She doesn’t need you? She deserves to lose a parent when she is a teenager? She doesn’t deserve for her children to have a grandparent?
Your job is done? Grandchildren who will never know you? Neighbors and friends that you will meet that will have a hollow hole in their lives?
Your job is done? God has a job for you. It’s there, a glimmer in the distance. Your enduring is a part of that job. Endure until he decides your job is done.
Frustrating, and frantic, and seemingly hopeless are lies meant to confuse and bring you to despair. Face them the same way you should face any lies. With truth and determination to remove those lies from existance.
Remove the teeth of those lies with statements of truth. Your job is not over! Your battle has just been joined! Your victory has just started!
Tomorrow, you get to a counselor. Your minister is a good place to start. If you don’t have a minister, getting one is a good place to start.
Get help, as soon as you can. You do not have to face the lies alone.
My BIL died at the age of 47 last year from heart disease caused by his life long diabetes. He left behind a 17, 16, and 12 year old daughter and a loving wife. Not a day goes by that one of them does not express distress over the loss of their loved one.
/sarc - If you really want to go only when your daughter does not need you any more, give her a gun and a single bullet with your name engraved on it, with instructions to shoot you when she no longer wants you around./sarc