Give me a break!
My thought on Weiner is that he is a very busy man. Like most, although not all, politicians, he probably spends a great deal of time going to meetings, raising campaign funds and seizing upon every opportunity to remind people of how great he is as a public servant and a human being. It's exhausting. He exists under a constant pressure cooker of self-analysis and public appraisal. Like other politicians, he needs something to take the edge off. For some people, regardless of occupation, that could mean booze, drugs, gambling, food or shopping. For high functioning men like Weiner and other officials who have lived through such scandals, who are constantly on the go, that leaves one tried and true source of a reliable high. The affirmation that comes when someone lets you know they want to sleep with you. Or even cyber-sleep with you.
This is sex for many people now. No time for Mateus and cheap spaghetti. No time for slowly moving toward one another with a combination of hope and caution, lust and integrity. One can push a button and get something beyond porn. Porn is essentially two dimensional. One sees and hears. Internet sexting can be perceived as three dimensional by adding the component of "feel", regardless of how cheap and unearned those feelings are. That person on the screen is doing whatever they're doing... just for you.
Weiner is so busy, he forgot the important rule that everyone you interact with on this plane becomes a co-conspirator. You rely on them to remain confidential.
Weiner is the modern, high functioning man. The fact that he is married is just one, albeit a huge, factor. I know many people who divorce over such issues of online betrayal. Appointment sex with your spouse doesn't always arrive when you need it most. A modern cell phone, loaded with contacts of willing fellow players, has a table with a red checkered table cloth ready for you at virtually any time.