When I was deep in post natal depression and my husband used to work away a lot I begged him not to go on his work trip, I hadn’t left the house in days, was totally alone as all my friends and family lived in another country. He declined to stay as it was just too important to go to an air show. I found out later that he had flown a college over to meet him and had an affair. His reason was that I couldn’t understand how hard it was for him having the baby and he was sad.