The impact of titles on a relationship (romantic, business, or otherwise) is an interesting topic.
Titles are basically a short hand for quickly getting across a number of general assumptions. The assumptions aren't always identical for a title from one audience to another, but for frequently used titles there are a basic set which most people are aware of.
This is John, my __________:
Assumptions:
Boss - please don't say "fuck" in front of him because he can fire me
Buddy - we have some kind of hobby in common (football, hunting, fishing) and hang out socially on occasion
Boyfriend - we've been dating long enough to decide we want to make a go of it, we are exclusive romantically and sexually
Husband - we are legally married, plan to stay together the rest of our lives, probably will have kids, and are exclusive romantically and sexually
We drop these titles to give everyone a basic idea of who this person is, how they relate to us personally, and to suggest how the audience might interact with them. It's not a perfect system, obviously, because the exact definitions of these terms are usually not discussed and they are pretty general.
When I bring someone out to meet my crew and I say "this is my friend, Carl", my friends can assume that I've vetted Carl, that he's not a complete idiot, and that I'd like for them to give him a break.
If on the other hand I say "this is Carl, we met online and I invited him to hang with us" this lets them know that I have *not* vetted Carl and that he's a wild card. If he turns out to be a jackass it's not my fault.
If I introduce IV to my friends as "my girlfriend, IV" unfortunately it provides them with a set of assumptions which are not all true. It's the same when someone asks me "do you have a girlfriend?"... they are not asking me if I have a partner in the way that *I* relate (which is an uncommon approach to put it mildly), they are asking me if I have a partner in the way that people *commonly* have partners. So while my answer to this question is "yes"... it's also kind of "no, not in the way you mean it"