What’s the worst date you’ve ever had, and why was it so awful?

Asked a girl out on a date. She invited me over to watch a movie with her at her parents house (we were in our late teens). I arrived; her recently deceased family dog and incredibly distressed mother were both in the kitchen. Dog was a really big golden retriever that had been euthanized, and the mom had bought him home? Not sure why? Maybe to bury in the back yard or something? Idk

Anyway I offered to leave but she was insistent that we watch the movie together, which we did, on the couch, with her mom crying in the next room. Halfway through the movie the mom screams he's still alive, he's still alive. Go into the kitchen, she'd gone to move the body and it had expelled air and made some noise. I had to explain, with my best year 12 biology, what had happened. Five minutes of this woman losing her shit with grief out of her beloved companion dying.

Girl insisted we watch the last 10 minutes of the movie, it finishes with us watching in silence, I get up to leave and said something stupid like hey I'd love to do this again sometime and she says "I have a boyfriend"

I'm like alright well that's that then and didn't put in any more effort. Stupid me, she was hot and I really liked her. Being a dipshit I wrote a song about it, using the three guitar chords I knew, which takes me to act ii.....

....five years later, I'm at a party, exchanging worst first date stories with friends and fellow partygoers including a cute blonde. I wait my turn, tell the story, she laughs her arse off and then goads me into singing the song, accompanying myself poorly on the guitar. I absolutely fucking nail it, everyone is in stitches, sit down next to her and the night goes from there. We end up leaving the party for a walk down to the local beach, made out on the beach, things get frisky, jump in a cab back to my house, in bed together, have drunken sex....which results in a broken condom. She lives literally the other side of town so we have to wait till (a) I'm sober enough to drive and (b) pharmacy is open to get a plan b, then have the most awkward drive back to her house. Get there, offer to walk her to the door, she says no, kisses me goodbye in the car, then texts me...to say she has a boyfriend.