Have you ever acted cooly towards a coworker because she seemed aloof and condescending, then gotten to know her better and realized she’s just shy and insecure? Or felt hurt when a friend forgot your birthday, then learned he’d been laid low by the flu?

These examples illustrate a central premise of cognitive-behavior therapy: thoughts are not facts. Our interpretations are hypotheses, and often—especially when strong emotional reactions are involved—they don’t hold up under objective scrutiny.

Take the assumptions we form during virtual interactions. Emails and texts notoriously lend themselves to drawing conclusions based on inferences— the meaning of an exclamation point or emoticom, say, or the absence thereof. It’s easy to read into the speed or length of a response, too.

Having been married for many years, long before the advent of Match.com, I never tried online dating. (Though a classmate and I did create a matchmaking inventory for a course requirement in graduate school. Too bad we were too shortsighted to realize its potential!) But I have no trouble envisioning the stories my mind would spin about possible suitors. My imagination has run away with me in situations where I have far less at stake emotionally.

I’ve talked before about my preoccupation with—OK, addiction to—Words With Friends. Mostly, I maintain ongoing games with people I know. But occasionally I get tired of waiting for them to make a move and seek out a random opponent.

I’ve developed a virtual friendship with one, whose screen name is “Amadbama.” Unlike many of the strangers I’ve played against, Amadbama kept initiating new games despite losing frequently, and by many points, to me. I was impressed by the sportsmanship and persistence. So one day, when Amadbama scored 109 points on a triple word play, I offered my congratulations.

Thus began our exchanges—just a few, impersonal comments at first, then some more details about where we’re from, our families, and the like.

This is where my assumptions started to get turned upside down.

At first I envisioned Amadbama as a young (because that’s probably the likely demographic for people playing games online), Muslim (because Amad has a Middle Eastern ring to it) man living in Alabama (‘bama). Then I learned he lives in Michigan.

OK, so the new geographic information required me to revise my hypothesis slightly. But it also bolstered my theory about his being Muslim because Michigan is home to the largest Muslim population in the US.

Then in a conversation about our respective Thanksgivings, Amadbama said he’d gone to bed at 8:00 pm because entertaining the six grandkids had been exhausting. I updated my mental image of him from a twenty-something to a bearded patriarch.

Recently I learned the truth (or, at least, what I assume to be true) about Amadbama’s identity: she is a 55-year-old woman named Susan. I was sorely disappointed to lose my multicultural friendship, even though it was only a figment of my overactive imagination.

And another thing. Susan’s game has improved dramatically, and she now beats me quite often. She seems like a completely different player.

I assume she must be cheating.