Jenna -
I'm so sorry you have committed all these stitches to your beautiful quilt. It will be a lot of work to take them all out, but you will be happier with the quilt in the long run.
I have had tension issues with my machine (still do) and it is frustrating. If you use her machine again you'll know to be diligent about watching both sides of the quilt and checking all your settings. At least the stitches shouldn't be hard to take out (as you and others have mentioned).
Darren