Plus one for

sam1252010

I was informed by a relative today that no adding a plus one to a guests invite is very rude if there is going to be a dance

SP29

Agreed ^^. Only those who are married, engaged, or in the long-term relationship need a plus one. 

MayberryAfterMidnight

I think your relative is confusing a wedding reception with Prom? (even then, it's perfectly fine to go stag...)

ETA: I can't believe I used the wrong "your" in my first post. *the horror*