So I did a search and can't find a clear answer. How do I address invites in these situations:
Unmarried couple living together (know the woman): Ms. Jane Jones and Mr. Bob Brown
Unmarried couple living together (know the man): Ms. Jane Jones and Mr. Bob Brown
Unmarried couple NOT living together (know the woman): Ms. Jane Jones and Mr. Bob Brown (and send invite to woman's address).
Unmarried couple NOT living together (know the man): Mr. Bob Brown and Ms. Jane Jones (send invite to man's address).
Is that right? Or is it the woman's name first no matter whose address it is sent to and no matter who is the person who is really being invited. Just seems odd to send an invite to Bob Brown, at his address, with Jane Jones's name listed first (and in some cases we don't know/never met the Jane Jones).
Thanks 
Edit: I did see one rule that if not living together they should each receive their own invite. I intend to break that rule, breach of etiquette or not.
Also, I am not using inner envelopes.