I started riding with a Tuesday-Thursday ride and those guys are mostly faster than I am. Well, that's okay. But this last time, I was talking to one of them, and turns out, he's hurting, too! It's not just me!
Anyway, 17 mph is faster than I normally average, and I got in about 8,000 actual road miles last year. So I'd say you're doing fine and just riding with the wrong guys. Go ride with some slower people and you'll get the warm fuzzies and be good.
If someone hasn't ridden any but is still an athletic person, it wouldn't surprise me if they could outride me, either.
__________________
"be careful this rando stuff is addictive and dan's the 'pusher'."