its not a sign in and of itself of anything other than what it is. A wife who is happy to provide you with comfy jammie bottoms. Don't attempt to read more into it.
Before we get off on another endless debate about whether or not to tell your wife, my question is "Do you want to tell your wife that you are a cross dresser?" Think about that question very seriously. After you've weighed out the pros and cons of telling her, and if you decide its something you want to do, then you need to think about how to tell her. There are a number of good resources here for that very thing.
