If you had had children, would it have been because you wanted to continue the line, or have the experience of nurturing and guiding a young mind.
I think most of us marrieds are going to be single, either through divorce or widowhood. Some will go on to have second relationships though I notice that these do not tend to be marriages. This is the dangerous time, esp. for women, who can be taken in by all sorts of love rats, just for a share of your property and your £.
An older friend of mine, who is now 70 and lives in Brighton, never married, never had a firm relationship, is an only child herself. As she was approaching 30 she decided to go for it by herself. She 'chose' someone at work, a doctor, and slept with him a few times until she became pregnant. She had a daughter, who has 3 children of her own now.
I can't say that my friend is a happy person, but her child did give her happiness when she was younger, but now her daughter's marital problems have inevitably impacted on my friend as well as the daughter's general lack of oomph - caused, I'm certain, by being mollycoddled too much.
She lives alone, which she prefers, and she takes two coach holidays a year, sometimes with a friend, more times alone. She is a very capable woman but says that being by yourself is not very stimulating. Not everyone is a joiner of clubs, but would still like a male friend.
But as you know, living as two is less expensive, and also married woman are usually better off financially. Two working people get a bigger mortgage and a nicer property, for example, and same amount of central heating to be paid for 2 as there is for 1, etc..