Author: I'm glad you wrote, I hope you are finding helpful ideas here. I'll be brief:
- Besides all the great ideas already here, consider religion. It can bring great calm. - If you have some talent in your job, just know that 'imposter syndrome' is real. Study it, you might get by. - If you have no talent in your job, start looking for something different. It's not worth staying in this case.
Wishing you good luck.