The past is a slippery beast, our memory distort and colour it and it lives in our minds and grows and enlarges and things that were bad become worse over time.
The past is past, it is beyond our ability to change it colours everything thing we do today and from this point forward. Sooner or later you will have to let it go. You cannot change it and cannot undo it so leave it alone. The path forward matters more, whatever your demon it haunts your words we all have them and no one can belittle or take it way I respect your beast.
Move forward what ever this event that created yours take away its power, go out of your way to help others do what you can to dampen the waves of your first stone. Do as much good for people not just your friends but people in general as the harm of your past find balance, find peace.
best wishes Alex