Originally Posted by DeniseP
Yup. A day late and a dollar short, just like always.
Oh Denise, you "sound" so chagrined with yourself it makes me sad for you.
Don't give up hope yet!
One thing to try is to take some tape (duct or masking) and dab it at the red spots. You may discover it's not really bleeding dye but just gobs of lint stuck in place.
If it isn't lint woven in, then try washing the quilt again, using LOTS of detergent and a high water level. If the red dye molecules are just staining the blue rather than actually molecularly attached to the blue fibres, the detergent and high water level will help them float loose again and stay suspended in the water.
If you try lots of detergent and high water level, be prepared to give it an extra rinse or three to get all of the detergent out.
If it were me, being a hand dyer, my third option would be to overdye with a light red, which would give the light blue patches a purple-ish tinge. I'd do it the low water immersion way, to get a lot of deliberate mottling.
And then if overdyeing didn't give me a look I was happy with, then I'd stencil with fabric paints or Shiva Paintstiks. If the batting is cotton, then the heat of an iron won't hurt it to set the paint or Paintstiks. If the batting is polyester, then I'd use Shiva Paintstiks, let them dry for at least a couple weeks (to polymerise as much as possible) and then toss it in a warm dryer to set the Paintstiks.
There's hardly ever a mistake in textile arts that can't be fixed, changed into a feature or transformed. And those are usually the pieces that turn out the most stunning!
I guess I'm trying to say that this is an opportunity, not a mistake to beat yourself up with.