This is the first 'golden rule' on surviving an affair:
Recognise that an affair is a symptom, not a cause, of a marriage in trouble. You've got to look for the reasons why it happened - what needs did your partner had that he was looking to meet elsewhere? What could you do to meet those needs within your marriage?
Really? Really???
So if your partner has an affair, it's entirely your fault? That's what that 'advice' sounds like to me. 
(apols if there is already a thread on this, I can't find one)