Not all men complain about marriage. I love being married - always have. I am in the minority though.
Most men propose due to pressure. Most men would NOT get married if women didn't want/need/insist on it. Just look on Y/A - "how do I convince him to marry me"?; it's been ....yrs and he still hasn't proposed, should I stay"? etc etc etc.
How many men do you know who have dreamed about getting married since they were a boy? Ever dreamed??
Men don't need marriage the way women do. Men don't need children the way women do. How many marriages and children do you think we would have, if it was up to men to decide???
You may not like what I say, but deep down, you must suspect I am right.
Women are the nurturers, men aren't.