Adult daughter has an eating disorder. How does her mother deal with the guilt she feels?

Adult children with compulsive behavior problems are growing by the thousands.  Alcoholism, drug addiction, anorexia, bulima, etc.  Why is this?  Are we recognizing the behavior patterns more quickly?  Is the pace and competition of our lives compounding this problem?  Do genetics and environmental surroundings play a role?  Yes to all of this, but added to the stress, pressures, financial burdens, medical and psychological issues, the emotion of parental guilt can be overwhelming.  Is this valid?  Is this fair?