OK, so as I think about this a bit more after taking the time to learn a little more, I have verbal palilalia and mental echolalia. Never thought much about the mental echolalia ... I always just attributed it to being a man.
If there is even a two second break in a conversation, I'm gone into my own thoughts. So if you start back up again, it takes me a second or two to lock back in. And I'll need to "rewind" what you just said while I'm kind of staring blankly at you. Frustrates my wife, but at this point, she recognizes it and will even say "rewind, play" herself. I'm still not entirely convinced it's not just a guy thing, but anyway ...
The verbal palilalia thing; yeah, that's weird and that's probably why I "cover it up" and only do it while alone. A couple of posters mentioned it's like rehearsing. I agree to an extent except that I feel like I'm endlessly rehearsing one or two sentences for a conversation I know I'm never going to have. Even annoys me somewhat but I suppose there's a reason I do it; in a way, I think it helps me work through various issues.