Normally, this kind of advice is framed more positively, but I want to be absolutely clear:
Don’t put yourself down.
Don’t apologize for existing.
Don’t tell others they should feel bad for knowing you.
Don’t wallow in shame.
Even if you feel bad, or like you’ve something to atone for, that kind of behavior doesn’t help you or anyone else; debasing yourself does nothing to process negative emotions or to take responsibility for your actions - and nothing hurts your loved ones quite like it.