So sorry for your loss. I don't think your idea is selfish at all and I don't think your grandmother would have felt it was either. I'm sure her concern was that the fabric get used rather than thrown away and I'm sure she'd be touched knowing that the family wanted this keepsake of her. It sounds like you and she have certainly contributed over the years, I think it's a tribute to your Grandmother to want this for yourself and the rest of the family.