I'd feel fine about it, but I'm not a particularly coupley person. What I'd do/ have done:
Make sure I was paying sufficient into a pension to ensure I had a good quality of life when retired. Being single is more expensive but equally as a single person you can prioritise where your money goes.
Make sure I had a will and it was up-to-date. If you die intestate with a spouse and children your assets go to them but without they go to parents, if still alive, then siblings, then various other family members who you might or might not want to inherit, so it's best to sort it out.
Take advantage of the flexibility of being single, so take opportunities in work and life, move around and try different things. Take a career break if money and retirement planning allow. Go back into education.
Write a novel, or at least try.
That's my take on it, anyway. I see being single as an opportunity to please myself and perhaps not get tied into the treadmill of modern life, which doesn't seem to make many people happy, but they have to stick at it because they have responsibilities which they have to honour.