How long has this been bothering you?
Have you had any evaluation to determine the cause of the double vision?
over most of my life originally not much concern but it has worsened as I get older
I had a bad fall aged 5 and a few falls over recent years
most likely cause of double vision when looking at up close objects is something we call convergence insufficiency. That is an inherent weakness of the eyes to be able to come in towards the nose when looking at near. We sometimes advocate something called pencil pushups, where you hold a pencil at arms distance and bring it in closer until you get double and repeat. However the easiest way to resolve the issue is to place prisms in your reading glasses so that it is comfortable to read and perform near work. I hope this helps Dr. Stevens