You cannot consistently betray your own plans and still expect confidence to stay.

Confidence is largely a record of your own follow-through, which means it cannot be maintained by encouragement while the record is being contradicted. Each abandoned plan is a small entry against yourself, and you cannot argue with a file you are still writing. The feeling of being unsure of yourself is often just accurate bookkeeping. That is oddly good news, because the file is editable.

Make your commitments small enough to keep, then keep them for two weeks without exception. Do not raise the difficulty until the record is clean. Confidence returns as evidence accumulates, not as a decision you make about yourself.