The problem I have with the word "partner" is that it is ambiguous -- it could mean life partner, sexual partner, or business partner. Honestly I wish there were another commonly accepted word I could use to avoid the ambiguity. "Spouse" comes close (if the couple is married) but there isn't a in well-accepted gender-neutral term for the other member in an unmarried pair. "SO" (significant other) comes close, but often I have to explain what that means, so I can't consider it well-accepted. And people seem to associate "partner" with sex, so if the couple is remaining chaste until marriage, using "partner" can be offensive. Sigh - English is hard.