Jeez, I see what you are saying, she does look naked and covering herself. Lets hope for her sake that's not really the case. I can't really think of anything more distressing than seeing the ghost of your mother naked. To me, it means she hasn't crossed over and she's in distress. If she'd crossed over, she would appear in a way that was comforting to the person she was appearing to. Maybe a little younger, maybe a little more bright-eyed and bushy tailed than you remember. Naked, well, I don't know you but somehow I doubt it.