Distrust on a Double Date

Me and my girlfriend of 3 years went out for the night with her friend (F) and her boyfriend

as a kind of double date. Throughout the night I noticed him giving her the eyes a little

bit. You know, sort of making eye contact a bit too much.

The issue is she was clearly doing it back to him. As the night went on it just got worse

and I noticed them holding their gaze even longer. I couldn’t believe it and it made me

feel so disrespected. i brought it up with her the next day but she completely denied it.

Calling me paranoid. I was sure what I saw, but she kept saying I had gotten it

completely wrong and that they had been friends since College. Has this happened