If you lost your signifcant other or a partner, but you weren't married, are you still a widow/widower or what is the correct term?

If you dated someone and lived together, built family and had kids for e.g. 10 years or more, but you weren’t married, they weren’t your spouse, what does that make you when they pass away?

Definition on Wikipedia says:

A widow is a woman whose spouse has died and a widower is a man whose
spouse has died.

I’m a foreigner and I can’t figure this out, what is the correct word, is it still widow/widower?