I think the worst and maybe the only bad thing I have done in my adult years was being verbally hurtful while suicidal.
Or when triggered by child abuse.
I am sitting here thinking about how sever it was. I didn't want people to love me. It felt like being forced to live. I don't do that anymore and I did apologize and mean it. While I still feel very guilty for it, I manage things far better now (mostly). Occasionally I lash out when it comes to children's rights.
It is tiring living in messed up world most people pretend to be fine. Makes me boil.