How frustrating!
Though I wouldn't recommend it, I enjoy unravelling yarn. I find it quite peaceful and soothing, one of those jobs that you just allow it's own sweet way. You don't have to make any decisions, just gently open the knots as you reach them and untangle each one. It's a job I might do when I'm not very well and not up to anything that requires lots of concentration. I like the sense of accomplishment :)
Hope you sort it, or put it away until you are ready to sort it.
I definitely don't recommend the cutting option! Imagine if you applied that to hair!