The problem is not your age, it's the time you have to devote to it.
As a child, you can spend all day doing one thing. Often, you are forced by an adult to do something you dont want to do for your own good. This leads to memorization of the skills needed
As an adult, you have responsibilities (you have to work, kids, errands, etc). You don't have as much time to devote to one thing, and you don't have someone telling you what to do.
So, your age doesn't have anything to do with learning an instrument, it's the time you have to spend on it. Learning to play takes a LONG time---years in some cases, but it is rewarding to no end if you can do it.