I need friendship advice.

So I have this friend who really only talks to me when she's going through a hard time. Hardly ever says a word to me otherwise. The other day I posted about being pregnant and how far along I was. She immediately comments "my god child's going to be the cutest". I've never asked her to be the god mother and just let it go. Then I posted something about the wedding date (trying to get a feel for the best time because my sister and I are getting married within months of each other) she immediately comments how she's the maid of honor. Again I've never asked her to be a part of my wedding! I have a god mother and maid of honor and bridesmaids picked out. And it doesn't include her, only because things seem to revolve around her and it gets a little tiring. I don't know how to nicely say "no you're not the god mom nor are you a part of the bridal shower" without her being totally crushed and upset. Help!? PS I really didn't know where to post this. I'm sorry!