This is a cry for help.
Girlfriend, boyfriend, partner, lover, significant other. We really don't have any good way to refer to unmarried romantic partners (see?) in English.
But first, let me explain why I think the status quo leaves us in such dire verbal straits:
"Boyfriend" and "Girlfriend" are terrible terms, for a few reasons. Firstly, by simply combining a gender and "friend" they imply that romance is simply friendship with one's opposite gender. Which is isn't.
Girlfriend is especially fraught, since lots of women make a point of casually applying it to their non-romantic female friends.
Both "boyfriend" and "girlfriend" also make it needlessly difficult to describe an opposite-gender friend with whom you are not romantically involved. I have resorted to "female friend" which makes it sound like some novelty, and I have also resorted to "girl space friend," which solves the issue, but really very awkwardly.
As many gay couples know, "partner" is equally problematic, since it sounds like a business relationship, and is indistinguishable from the same during introductions.
Lover is at once too emotionally mushy and too explicitly sexual. Here I'll quote Catch-22 author Joseph Heller making this point rather lewdly and with characteristic comedy: "I used the word [lover] only once in a book, when the character Gold is reacting the way I am and the woman says, 'You are my lover.' He never though of himself as a lover. he says he always thought of himself as a fucker, not a lover."
That about says it all.
Lastly, "significant other" is especially terrible. Where to start? It suggests that, for anyone, there is only one significant other, and that a necessary condition for significance is romance. Anyway, what a lot of people value so much about romance is that it does away with the very feeling of other-ness. But worst of all, it's just extremely cold and humorless.
This shouldn't be so hard! Fiance, spouse, husband, and wife all work perfectly.
So what do we do? The french have "petit ami" (little friend) for boyfriend, which is at least funny.
I'm out of ideas. If anyone else (an "insignificant other"?) shares my aversion to the syntactically and verbally awkward words we use for the people we love, please suggest some alternatives.