Hi Jeanice, and Welcome to the Quilting Board from a quilter in sunny Nevada! We're a great group here, and I hope you find yourself right at home.
I was thinking about your silk Cathedral Windows, and thinking that if your fabric is a bit too fragile for a quilt, perhaps you could do it as a foundation piece. With something permanent like another fabric as a background, and the silk stitched on top of that, there would be no concern for stretching or sagging out of shape. Just a thought. Paper piecing wouldn't have the same advantage because the paper is isn't permanent, it's removed obviously.
Would really love to see that project as a photo when finished!
Cheers!