A Little Lie That Haunts Me

I was always careful not to cross the line but one day, I just couldn't resist. It was a coffee run for work when my ex was supposed to be handling it. Instead of buying her usual drink, I got us both something completely different and enjoyed watching her confusion when she took a sip. She never figured out why I did it, but I can't shake the feeling that I betrayed our friendship in some small way.