This is exactly the reason I always set the dyes in the fabrics I use for quilts! Not that I'm all that experienced, mind you, being still a rank amateur. I have the fabric all dye-set, washed, dried and ironed for a log cabin quilt. I spent about $300 for the fabric alone. But it's reds and whites and despite anything you do (just about) red will bleed. I discovered the Rit dye-setter almost by accident (honestly, I don't own stock in the company or anything), but I'm a believer. It also works for those who want to hand-paint! Enough said. It's a tragic thing to have a quilt bleed to that extent! I am so sorry this happened to you.
Jeanette Frantz