As I sat through the “How well does the bride know the groom” game, I realized that I would have scored higher than the bride had the questions been about my roommate and BFF, Lauren.

Lauren and I are so close, we’ve considered adopting one of those cool celebrity hybrid names to save time. Lyndsen? Laurdsday? (Official celebri-name and pregnancy/adoption rumors pending).

We know each other’s weekly schedules. We call each other on our office lines and we often are the other’s “plus 1” at weddings and office functions.

We take turns buying milk and often plan weekday meals together. We have bizarre pet names for each other—Bobo, Sheesh and Billybob Thornton, to share a few.

Sound familiar? When you’re single, the people closest to you take on the role of what I like to call the “SSO” (surrogate significant other)—whether it’s your roommate, office mate, sibling or best friend.

And it’s not just a female thing. Take, for example, my two very heterosexual friends Nick and Russ , who have a beautiful bromance. Most weekends you can find Nick spending the night at Russ’ or vice versa. And more often than not some form of baking is involved. I’m not kidding.

I recently overheard them discussing the idea of Nick keeping some work clothes at Russ’  place, just in case he ever needed a change of clothes. I told them that the day Nick has a “drawer” at Russ’ they officially need to change their statuses on Facebook to “It’s complicated.”

So am I saying there’s something wrong with this? Absolutely not. But just in case you are wondering if you’re in a similar situation, ask yourself the following:

>>Have I recently rented the entire “Lost” series to watch with this person on the weeknights?

>>Have we tattooed each other’s middle names around our navels?

>>Do people refer to us as a BOGO (buy one, get one) behind our backs?

>>Do we have a pair of jeans that we trade every month that magically fits us both and inspires us to greatness?

If you answered yes to any of the above questions, congratulations, you have an SSO. But don’t panic.

These close, “in-the-meantime” relationships are perfectly healthy. Take me and Lauren for example; we are still roommates, we still get wedding invitations addressed to both of us, and may or may not be planning a Caribbean cruise for 2010.

As I see it, these relationships are good way to about yourself  and what you need from a significant other. I already know that I need a man who loves to clean, tolerates my daily 5 p.m. napping habit and is willing to call me “Billy.”