Heather, I have convergence insufficiency. I wasn't given that name for it until just 2 or 3 years ago, actually. I always wondered why the eye doctors said "tell me when you see double" for parts of the exam because, well...I pretty much always see double unless I "pull my eyes in" as I've always called it. I just figured that everyone had to do that and so I never said anything about it. It wasn't until an eye exam with a fresh-out-of-optometry-school doctor that I found out I had anything abnormal (beyond astigmatism) going on. He noticed that when he would cover one eye and then the other while I stared straight at a pencil in front of me the eye that was uncovered would "jump" back toward center to focus. I guess that's not supposed to happen?
Anyhow, vision therapy was suggested but as an adult it's not something I'm interested in, nor is it something likely to actually work with as old as I am. And vision therapy is also a controversial thing in the vision world. The eye clinic I saw in Oregon has a doctor who really pioneered it and super much pushes it. The one I go to here in Wisconsin, my doctor knows my old one and went to school with her but flat out disagrees with the premise that vision therapy will do anything for anyone with this issue. I have glasses with prism lenses for working up close and those are AMAZING. I can relax and not have my vision go double for the first time EVER! I can't use them for driving or really anything beyond computer and deskwork or reading, but I am so happy to have them.