Why do some people with disastrous marriage try to convince single people to get married?

I’m not against marriage at all. I’m, in fact, pro-marriage. It’s just that I don’t understand the logic of married people with disastrous marriage when it comes to settling down. They complain about their marriage, complain about their cheating spouse, complain about their spouse running away and leaving them with someone else, but recommend single people to get married.

While I agree that, ideally, it’s good for a person to settle down, it’s not something that should be done just for the heck of it. Some married people look at single people with a feeling-sorry-for-single-people look and try to “console” single people by saying, “don’t worry, being single is also okay” without being asked. Doesn’t that sound condescending? Also, don’t they realize that they don’t serve as an inspiration to single people to get married? I rarely hear happily married couples bring up marriage to a person who’s single and try to pressure that single person to get married. Sometimes it makes me wonder why unhappily married people are the ones who keep bringing up marriage more often to a person who’s single, especially if that single person is in his(her) late 20’s. Single women are the ones who get mostly bombarded and pressured with words like, “you should get married”, as if the only thing a woman needs to do is pick someone at random and get married. I mean, hello, what are they thinking!