My grandparents decided to learn Welsh when they were 65. After two years of lessons in it (and talking Welsh with me at home, I was going to a Welsh school and was already fluent), they were fluent. My grandmother, around the same time, decided to overcome her phobia of water and had me teach her how to swim. She'd swim laps with me in the pool up into her 80s.
You're not too old and it's not too late to try something new.
This is a thing I'm still working to convince myself of regularly -- it's a bit more uphill for me regarding some things, but I'm currently leveraging my mostly-text-oriented brain and learning Japanese to be a translator (and maybe someday write for native Japanese audiences) as well as Spanish, German, and Brazilian Portuguese conversationally. (and I'm trying to get a smidgen of Russian in there too!)
yeah, it's a little weird for me to think about, so I usually just don't think about it ^_^
@sydneyfalk gosh! So many! :D