Used to means that you (or she) don't (or doeasn't ) anymore, and often implies some feeling of regret when used in the first person (i wish were still playing piano), with apropriate tone.

'Would' in "when she was younger, she would play piano at church", is used to describe something that was a regular occurance, and further frequency (or lack there of) could be emphasied with "sometimes" or "often". Basically, you're making a general statement about the past.