I know that in my hectic schedule (and I don't even have a wedding added in) I get focused on the latest crisis and lose track of what I needed to get back to three or four interruptions ago. Most likely she has misplaced your phone #, not finished the quilt and forgotten exactly what you agreed on, since it was a rather nebulous agrrement anyway.
I think your best bet is to give her a friendly call inquiring about the progress of the quilt and the wedding preparations. I'm guessing you'll get a reply full of how busy, hectic, chaotic things have been and an apology for not getting back to you sooner.
My personal choice would be to consider the fabric a wedding gift, whether or not she offers to pay. But that's just me.