Some great advice I got from a therapist when we were discussing guilt over past actions and behaviors (some paraphrased, some written down during session):
“You only ever realize you did something less than ideal once you’ve grown past it. So if you find yourself thinking, ‘Wow, I was a terrible person,’ or ‘Oh man, I did this rude awful thing,’ try reframing it as: ‘Wow, I’ve grown into a much better person now,’ or ‘Oh man, I am a much kinder and more understanding person who knows not do something like that again.’ Nobody starts out perfectly kind and reasonable, and it’s worth recognizing and celebrating when you’ve grown as a human being.”