That is a tough situation, because like you said, it's really nice that she's thinking of you and trying to help but it also sounds like she is really going overboard. Obviously she's excited so maybe you can plan something fun to do with her. If she wants to go shopping, you could say something along the lines of, "I already have everything I need besides a changing table and a carbut I would like to spend time with you...why don't we spend the day at a spa?" I mean if she's obviously willing to spend a lot of money on these babies I'm sure she wouldn't mind paying for at least her own spa treatment, ya know? That would also be a good time to mention the handmade things..."I have everything I need but I would love one of your handmade blankets/pillows/curtains/whatever she makes"