I never comment, but your post really touched my heart – I’ve been where you are and I know how you feel.  Here’s what I did:

1. I asked myself “what’s the worst that can happen if I leave my job and do what I really want to do (pursue a career in the arts).  I realized that the worst that could happen was that I might end up living in my car.  As unpalatable as that sounds, the thought of spending my life at jobs that I hated was even more unpalatable, so I came up with a plan:
2. I reduced my overhead as much as I could so that I could afford to live on less.
3. I found a lower-paying job that I didn’t hate, and that allowed me the flexibility to start building a life that I wanted.
4. I worked my BUTT off – day job by day and classes, workshops, and free work at night just to build my artistic career.
5. I now have a professional artistic career that has supported me financially for the past 12 years.

You can do this.  Your life is bigger than any one job.  Seek therapy if you need it – your therapist can be an ally in helping you to come up with a viable plan and holding you accountable for following through.

Whatever you do, don’t give up on life, and don’t let anyone else determine your worth.  Own yourself and your decisions fully, and get into the driver’s seat.

I would say “good luck” but it’s not luck.  It’s goal-setting, determination, persistence, and hard work.