Essentially what you said, but I'd like to phrase it the way a counselor said it to me when I was under a lot of stress at work. Stress is the gap between our expectation and reality. Say you expect to be/produce/achieve/whatever 100%, but you are only capable of achieving 80%. The stress you experience is that 20% gap. Change your expectations to meet your reality and that stress will be resolved.
Now, it may still be that others might still want or expect that 20% from you, but that's their problem and their stress. If you cannot produce it anyway (which created your stress in the first place), existing in the stress-gap clearly won't make you able to do it anyway.
This happened to a young man I knew who was trying to get into HVAC. He had to start all over again and find someone new who would actually sign his hours. He eventually did, but I could just add easily imagine if it didn't happen.