In shock scenes, Binky smacked Alex around the head after he was confronted by Lucy Watson and Louise Thompson at Stevie Johnson's surprise birthday party.
Lucy had earlier been told by Jamie Laing that Alex and Spencer had "hooked up" with several girls on a night out, and she and Louise forced him to admit the truth at the garden bash.
Alex confessed to cheating on Binky again, although he said he couldn't remember if he'd actually slept with them as he was "slaughtered", and she walloped him on the side of the head.
Ahead of the show being aired, Binky tweeted: "My hand hurt a little in this ep! Not watching it dudes- too depressing for a Monday for me!"
After watching the episode, This Morning's Holly Willoughby - who is a big fan of MIC - took to Twitter and offered Binky her support.
Mark my words... Alex is trouble personified. Just want to scoop binky up and take her away! #mic x— Holly Willoughby (@hollywills) May 19, 2014
"Mark my words... Alex is trouble personified. Just want to scoop Binky up and take her away! #mic x," she tweeted. Binky then replied: "Yes please x."
Meanwhile, Alex had simply told his fans: "Enjoy the slap, sure you've all been eagerly waiting."
This latest bombshell comes just a week after Alex finally admitted to cheating on Binky several times in their relationship.
Surely she's not going to take him back now? Only time will tell!