To ask why I can't invite her?

[HiiiPaigehere]

Meeting up with ex work colleagues this week for a meal. When I worked there, it was comprised of three receptionists (I was one) and three dental nurses. Now there are still two receptionists there who I know and one nurse (other two have left.) I asked if I could invite the one nurse I know to the meal. They said that if I do then they'll have to invite the other two new nurses. Why?
I don't know them, they don't know me. It's not a work do its a meal with friends?
AIBU?

Is she a friend, or a work colleague? If she's a friend then surely you're meeting up with her sometime over Christmas anyway?

If it's going to complicate things for them, or potentially cause ill feelings, then you have to stick to the original plan.

It does sound that you are missing people out, if you do it your way.

It’s not a works do as you don’t work there, why would they expect you to invite folk you don’t know? Just invite your friends, I doubt the new nurses invite colleagues friends out 🙄

You only invite the people you all know to events like that.

The other two nurses dont know you and if it's explained to them that it's a meal with you (the ex colleague they don't know), they should be able to grasp that. Whether or not that will happen though...