The reason it’s called thepast is because it’s done; it’s over; it’s history. Now do your part and let it go. Don’t hold on to things that are not productive. If it ain’t helping you; if the past is dragging you down; then find something new and better to do.
Don’t waste your time feeling guilty, trying to fix what you can’t change. Admit your mistakes, make amends and move on. It is selfish to continue to punish yourself and those around you with things that have already happened. Look at the present, look to your future and start moving towards your goals.