I will be thinking of you this week.
Please know that it is not your fault. When I lost my mother last year I did the self-blame thing. Its natural. It took me a while to be convinced that it wasn't my fault-I don't have a crystal ball that looks into the future. I only acted on the here and now based on what information I had at the time. The same is true for you. There is no way you could have foreseen this.
Again, know that your family is in my prayers.