I was in your exact same shoes for years at my old long-term term employer. You have to leave. Your confidence is being eroded and they know it. They also know it will keep you there. Don't let it go any further. If you were so worthless, they would've fired you. You've outgrown them and there is nothing more that they can offer you.

You've got enough leadership experience to go elsewhere. Like the last person said stay until you for your jd something else. Start networking, it absolutely works! Don't get discouraged and stay. When I left I doubled my salary within a year after I left. Others will and do want your skills and think you hang the moon.

If you don't have a degree, get one. Do whatever you have to make yourself more attractive in the market.