Aww, sorry you are having problems!
all of that is so frustrating, I agree!
Do you have some other yarn that you can just start another project?
Also, what have you tried to use to get the stain out?
I don't know what kind of yarn the stain is on, but I use "Dreft" stain remover, pretreater, on stuff I don't think I can get out...and 90 % of the time it works! You're a grandma too, you might already use Dreft, it's great on baby stains!
Hang in there!