I didn't think I'd ever want to. I was financially independent with adult DC, a happy single life and very active social life. I couldn't see any benefits to having a man in my life and only risks in marrying one!
Then I met a man who has changed everything. I'll spare you the soppy bits, but he makes me very happy and we spend a lot of time together, at home and travelling.
He's never been married. I know we can't marry, to protect my DC and to prevent things getting complicated for them and he understands that, but I'm sad that we can't.
We cannot even live together without things getting complicated. A friend's mother has recently died leaving her "new" partner of 17 years in the house. She left a will protecting her DC, but giving him the right to stay in the house while he needs it. So the DC are now faced with an indefinitely delayed inheritance and the "agro" of having him living in "their" house. OTOH she'd lived with him for 17 years, presumably she wanted him taken care of, which people here don't seem to understand when they talk about parents' estates.
Anyway, we'll carry on as we are, but it does sometimes seem a shame.