(one's) better half
One's spouse or romantic partner. I'd love to come out with you guys after work, but I'd better check in with my better half to make sure we don't have any plans for this evening. The work retreat is meant to be for couples, so be sure to bring your better half!
your other half
or your better half
COMMON If you refer to your other half or your better half, you mean your husband, wife, or partner. They invited us out to dinner after the election because they said it was time they met my other half. It's a shame my better half isn't here. You'd have someone to gossip with. Note: These expressions are usually used humorously.
your better half
your husband or wife. humorousyour better/other ˈhalf
(informal, humorous) your wife or husband: I’ll have to ask my better half about that.