Hi, my fiancée and I are getting ready to ship off our Save the Dates and we're trying to figure out etiquette and protocol for addressing the envelopes. We only have the outer envelope, no inner envelope, and there's no personalization on our actual save the dates. We live pretty far away from all of our friends and family, so pretty much everyone would need to travel and we want to make sure they have adequate time to make arrangements.
The question we have is how to deal with plus ones. For married/engaged couples or people in long term relationships who live together we know to address the envelopes to both of them. But for single friends in short-medium relationships we aren't sure how to make clear that they're welcome to bring their significant other or a date.
one idea is to address the envelopes to "Jane Doe and John Smith" if Jane and John have been dating for a while, but that seems odd to send to Jane's address where she lives without John, and could cause confusion if Jane and John break up before the wedding. It also doesn't solve the problem of how to inform guests that they'll be able to bring a plus one if they aren't currently dating anyone.
The other option we're considering is some sort of insert in the envelopes that make clear who we would be inviting, either with the name of the significant other or "Jane Doe + Guest", but that seems like it might be tacky.
Or should we not even be thinking too much about Plus Ones at this point, and just address the Save the Date to "Jane Doe" and wait until we send the invitations to worry about Plus Ones?
Looking for any advice we could get here. Thank you!