Don't beat yourself up so much; some things are just meant to happen the way they did. We even have people here whose traditional names loosely translates to, "things that happened, happened just the way it should." I think some of these things will happen if it was meant to be with or without your effort to stop it. The life we live is not fair, some things that life throws at us is just straight out of Unfair Land. My condolences to you on the loss of your friends and others we have lost in this journey called life.