I take the song to be about where she is NOW. It can change. I mean, Gene Simmons just married Shannon Tweed after what, over two decades?
All of this could fall by the wayside if she meets that "someone", as it will for me should I decide to again(I was married once). When you're in love--really there--the decision can be incredibly clear.
I know married people who are happy. I know people who just live together who are miserable. There is no science to it. I say, do what is good for YOU.
I see so many people who are influenced too much either by tradition or the so-called "progressive" bucking against it and never really look inward to find the truth and what truly works for them. It is no one's beeswax except the people involved.
I dunno, IMO I feel that being married kicks everything into a different, higher gear than just living together. It's like saying "I'm not in a BAND, I just play music with 3 or 4 other dudes", like where is the identity of the union?
Dan/NS