Physical & Emotional Abuse Support Group
Abuse is a general term for the treatment of someone that causes some kind of harm (to the abused person, to the abusers themselves, or to someone else) that is unlawful or wrongful. No one deserves abuse, period. Abuse can be emotional, physical, or sexual.

That "independent" contractor title is a big deal. It's the difference between a guaranteed salary and taking whoever they give you, vs their ability to drop you on a dime, and your ability to pick and choose.
If they throw that line about "getting out of work" at you again, just reply:
"Exactly. My ability to know and set my own boundaries is a huge part of being good at this job."