Is she crate trained? If not, I'd start working on that right away. A crate the right size for her will discourage her from using her sleeping space as a bathroom. If she's timid, it may help her that way too - many dogs view the crate as a "den", and enjoy being in it because it provides them a safe place of their own.
Otherwise, I would keep potty training her as you would a puppy. When she potties outside, reward and praise her. Remove her water dish passed 8pm or so. If it helps to get up with her in the middle of the night once too (our 9-month old sometimes still gets me up in the middle of the night to go out) then that's another opportunity to praise her for going outside.
Warden - Sable GSD 4/23/2013
Blackjack - Black and tan GSD 4/23/11-6/1/2012