I don't see why she would HAVE TO be in her crate while you're showering. When Fozzie was a puppy, he used to hang in the bathroom while I was showering and getting ready.... sometimes, he even hopped in with me! ; ) As long as your bathroom is safe, puppy-proofed, she preferably has a toy or a chewie to occupy her, and she potties outside right before you shower.
The key to potty-training is not even giving her the opportunity to potty inside. Take her out more than she needs. Two times more than she needs. Three times more! When Fozzie was 9 weeks old, whenever anyone was home, he went outside to potty every 30 minutes. Yeah... it is overkill, but he learned that he got treats when he pottied outside, so he looked forward to going out. He also got plenty of exercise and leash experience, which is important as well.