TTCinBC. I hear you - the nesting impulse is strong and very hard to fight. Whenever someone asks if I'm excited for August to come, I kind of panic inside, too. Yes, I am excited - but all I can think of for the moment is the million things that need to be done first! In the beginning, all they really need is mommy/daddy, food, clothing & diapers. I've started entertaining the idea of the nursery not being 100% ready when she arrives to help calm me down a bit. She'll be in a co-sleeper with us for a while, so its ok. I mean, I want everything to be my idea of perfect at home before she comes, but we'll see how realistic that ends up being.
Anyway, good for you for trying to let your mother help the way she wants, even though it drives you crazy. I wouldn't blame you at all for giving her a deadline, though. Its not exactly something that is in stock on a store shelf.