Therapy and meds. At some point you need both. One to change chemistry in the brain (meds) to properly rewire your brain (therapy).

High stress mixed with some thought loops is doing exactly the same. It changes chemistry from baseline and rewires your brain. Often for worse.

Regarding #3. Consider this. You break your hand. Would you be questioning yourself over using the other hand for daily tasks? You break your foot. “I should be walking faster” is doing what good in that moment?