orima-kazooie said:

It’s probably relevant to mention this is assuming the spouse knows you won’t get along but has nothing against the partner coming. Or are you supposed to invite them and let them/hope they decline?

little-mourning-magpie said:

In my experience this is only ok if you do the same to everyone. So you can say no partners but not specifically uninvite one person’s partner if other partners are coming.

realsocialskills said:

I think that it works like this:

• If you invite a coupled person to a party, the invitation is generally assumed to include their partner unless explicitly stated otherwise
• It’s usually considered rude to explicitly uninvite someone
• Partly because it’s considered rude to tell people about parties they aren’t invited to
• But it’s considered ok if there’s a general reason partners aren’t invited that isn’t personal, because then it’s not an insult
• Eg: if no one’s partner is invited, or if it’s a single-gender event and the partner isn’t that gender

Just to be clear, I don’t think it’s always wrong to be rude in this way. Just that it’s a convention it’s worth being aware of, because ignoring it can have unintended consequences.

A couple of situations in which it might be a good idea to violate this convention:

• The person you don’t want to invite is or was abusive towards you or someone you’ll be inviting
• The person you don’t want to invite ruins parties by telling racist or misogynistic or otherwise hateful jokes, and has repeatedly refused to knock it off