Hi,
You give a wide date range 1650 - 1699, which covers a number of Kings not to mention the 11 years when we became a republic 1649-1660.
Mary wife of William of Orange ruled from 1688 - 1694.
If your ancestor was a Lady in Waiting, she would have been from upper class/titled family, and more than likely married into the same class. If you have her name, and possibly her title you should be able to discover more about her.
Spendlove