Funchy- a nitpicky point- In the US, common law marriage these days may only be contracted in DC and 11 states. States are rapidly phasing it out by statute or case law and frown upon it in general. It's a misconception that you can simply 'become common law married' after living together 7 years or whatnot. Even in states that recognize it, there still must be a general holding out of being married, along with an understanding between the couple. Otherwise the bf and my other roommate would be halfway to being common law married to the two of us (a whole other polyamorous can of worms we've never explored)
But I think the real issue here is that the OP sees marriage as signifying some kind of commitment unattainable by unmarried people. Or something like that.
(this message not intended to be legal advice of any sort, just fyi)