I don't think it's selfish at all, but I can understand why you have twinges of guilt - I probably would too. It's a funny old thing.
I don't think you need to, but if it helps you, make another quilt from your own stash for charity and label it, 'In Memory Of.........'
Or if you don't have the time, you could give a small donation to a charity she would like, as she was clearly a charitable woman.