What I am sick of is this 'single women are soooo much happier than married women' bullshit. As someone said, this 'study' which probably only polled 1000 of each, is 60 years old.
I am very happily married (over a quarter of a century!) and many other married women I know are very happy too. Conversely, most single women I know are generally miserable and lonely, and struggle financially, working every hour God sends to make ends meet. They are not all on £90K a year, and living in a swanky London apartment, in a high flying professional career, with a dozen friends, and a glorious social life, and taking several holidays abroad every year. Most are on the national minimum wage, they have not got a pot to piss in, they can't afford a daytrip to Rhyl, and as I said, they are very lonely.
And some people say 'men have affairs/men cheat while their little wifey is at home being the dutiful housewife.' Do you think the wives of these men don't have their fun too? 
As has been said, men AND women have affairs. Some men I know who have had affairs, had then with a married women! Not that many have them with single women.
And shocker! Some married couples don't have affairs at at all, and are happy together for many years. Yeah marriage has its ups and downs, but on the whole it's great to have someone to come home to, someone to cuddle up to at night, someone to laugh with, someone to cry with, someone to care for you when you're ill, someone to go out to dinner with/to the cinema/to the theatre/on a daytrip/on holiday. And you can share life's trials and tribulations and the financial burdens. 2 incomes makes life MUCH easier and more pleasant.
Better than being alone, struggling financially, no-one to share anything with, no-one to help you if you're ill, no-one to go away with on holiday etc, and no-one to talk to at night, and no-one to cuddle on the sofa. Yeah I am sure some people will say 'I have friends!' But the fact is, most people are in relationships, so the amount of people to do anything with is very limited.
People do love to bleat this 'single women are happier than married women' trope. Fact is, it's simply not true. Many single women are lonely (hence so many on online dating sites,) and they struggle financially, and are constantly having to work more hours to make ends meet.
Is that a presumptuous and offensive thing to say about single women??? Maybe. Imagine how fucking annoying it is (as a married woman,) to keep hearing that single women are soooooo much happier, and married women are miserable, downtrodden domestic servants to their ever-cheating sleazy husbands. I'm sick of it. It's not true, and it's something single women tell themselves to make themselves feel better. Some people go on about 'smug marrieds!' SMUG SINGLES are worse! 