I'm very attracted to my co-worker -- a self-described "happily married man." We are "friends," but he always has a warm hug, an interesting YouTube video, or a poem or short story he's written to share with me. He has taken me to lunch and has done work for me gratis. If I have car trouble, he connects me to a mechanic and sees I get great work for a great price. Twice he's told me, "I love you." The second time, I responded, "I love you, too, and if you weren't married, I'd take you on!" He then responded, "Previous commitment!" I'm confused as to what's going on in his head. There has been no sex, and he hasn't asked for any.

--Huh?

Nothing says "I want to make mad, passionate love to you" like a referral to a skilled and honest auto mechanic.

The guy seems to be having a "flirtationship" with you -- which is to say, this stuff he's doing is foreplay to foreplay that's unlikely to happen. There seems to be some evolutionary psychology bubbling up here -- specifically, a facet of "error management theory." This is the mouthful of a way that researchers Martie Haselton and David Buss explain how, when we might make an error in judgment, we evolved to make the least costly error. And though women engage in flirtationships, men seem to have evolved to err on the side of not missing a possible mating opportunity. And yes, that's true even when they aren't technically free to "mate" -- like when a guy has taken (and seems to adhere to) those pesky vows to grow old with some lady, and not just in between sex romps with some other lady.

That's where flirting comes in. Interpersonal communications researcher David Henningsen points out that the essence of flirting is ambiguity, leading the target to "suspect that sexual interest is being expressed" but not allowing them to really be sure. As for a flirt's goal, predictably, for many in Henningsen's and others' research, it's about "getting some." But some flirting, called "instrumental" flirting, is about getting something else -- like getting a discount, getting some free help, or getting out of a ticket by flashing a lady cop one's man boobs.

As for what may be going on here, Henningsen notes that some flirting is just about having fun or is a way for a person to feel good about themselves. ("She's all over me like ants on a croissanwich!") There's also what Henningsen calls the "exploring" motivation: safely testing what a relationship with somebody new might be like (in case the wife runs off with the census taker).

Chances are, this guy is into you but is clinging to fidelity like a shipwrecked rat on driftwood. Maybe try to enjoy this for what it is: free lunch, free work, and referrals to the amazing Carlos at Numero Uno Auto. And try to be grateful for all that he shares with you, like the poetry and short stories that his wife probably (wisely) refuses to read. As for a companion to take you to that dark place with satin sheets, you'll have to find somebody unmarried and available. If this guy is looking to make his wife cry, it seems he'll stick to low-grade relationship misdemeanors, like forgetting her birthday or, when they're in bed, calling her by an old girlfriend's name. Or by the dog's.