How to live with guilt

Hi, I know I've already posted sth similar here. I've recently made some poor decisions that hurt me and my family. I didn't commit a crime or anything, just made some poor decisions out of stupidity. I know it's all in the past but the guilt is eating me alive. I have this feeling in my stomach that won't go away. I am constantly thinking about how this could've been prevented and how my family shouldn't have suffered. I don't know how to explain my behavior except that I was acting a certain way because everyone was expecting me to act that way(?) Also I am an idiot.