I disagree with your daughter as well. This is your hobby and no different than if you loved to golf or something like that. Yes, there's a cost involved, but it's what you love to do. I also agree that you need to keep it within reason and if you're getting into serious debt, it's time to scale back on your golf game, so to speak. Save the quilt.
You know that there will be a special child in your future. You just haven't met him/her yet. But I promise, an opportunity to share this with someone special will come.
Don't give up your hobby - keep quilting - and we'd all love to see pictures of this latest project! Please post!