Sometimes it is not easy to tell what are personal faults and what are something else. I worked for a long time thinking I was not doing as good a job as expected, the others did better or quicker, and that my actions could lead to my boss being displeased or worse. I felt I was simply not up to expected standards.
These feelings then spread to my home life and matter deteriorated.
In the end I was diagnosed with an anxiety condition and started to get medical help. Now, looking back I can see that that habit of low self esteem and confidence, and worrying about past events and future disasters due to my actions were in fact all the product of anxiety.
Until I got that support I simply kept on going downhill. Thee was no way I could make matters better by myself, no matter how hard I tried.
Now I am in a very much better place, I still take meds and see a psych, but that has been going on for years and is simply part of my daily life -I'm good, my work is good and my family gets and gives support and love.
Unless you are already doing so may I suggest you go see your GP in a long consultation and say how you have been feeling -then take it from there.
Trying to handle this all alone is very hard. Do you have anyone, family or friend, to lend you personal support? someone you can talk with and gain perspective and care?
I hope to talk to you again