The wrong person can make you question qualities the right person will thank you for having.

Being with the wrong person can turn your best qualities into faults: your sensitivity becomes too much, your ambition becomes selfishness, your honesty becomes a problem. Hear it often enough and you begin to believe the trait itself is the issue. The same qualities are frequently the ones someone else values most in you. It was the fit, not the trait.

Think about what you have been criticised for repeatedly and ask whether it is a genuine flaw or a mismatch. Test it against people who know you well and want good things for you. Some of what you have been trying to fix does not need fixing.