Know it is not your fault.
Keep a journal.
Get clear about your boundaries.
Do not allow yourself to become drained, and do not feel guilty for needing to take time away to recharge.
Try to find something joyful in every day.
Control your own finances.
Be good to yourself.
People may have told you to leave, but you need to trust yourself to know what is right for you, and when. In time you will know.