I'm sorry to hear that, it sounds like a horrible thing to happen. I don't think you deserve to be so hard on yourself though. It isn't your fault that the people who did know about it didn't show up! No-one else is angry with you, and I don't think you deserve to be angry with yourself - though I know it isn't that easy. These things do happen though, and you can always use it as something to learn from. Try to look after yourself.