Ex partners often feel miserable at the idea their significant other can get on with-out them. I am guilty of this to a degree myself. Though I left because my spouse was already having a life that didn't include me it still bothered me that he was doing well once I was out of the picture. For me it only confirmed my suspicion that He felt I wasn't needed and I was very troubled by this. I had hoped there would be a period where he would not do so well. It would have made me feel vindicated. Instead I felt like such a loser. Now, I stopped short of the 'stalking' things like Facebook and trying to find out what he was up to. Still, his getting on quite happily without me was difficult.