AITA for making my cheating ex’s life a living nightmare by messing with his food?

So, my ex (32M) cheated on me (30F) with my best friend. I found out when I walked in on them at my own birthday party—in our house, in our bed. Instead of apologising, he told me it “wasn’t serious” and that I should “grow up.”

Fine. I grew up. But I also got petty as hell.

We still lived together for a few months after the breakup because we were stuck in a lease. During that time, I started messing with his food in the most disgusting ways possible.

• I stirred his protein shakes with dirty socks.

• I put laxatives in his pre-workout drinks.

• I swapped his regular coffee for decaf, and he couldn't figure out why he felt so tired.

• And my favourite? I licked every single one of his sandwiches before he ate them.

  
  

By the time he moved out, he had no idea what I’d done. But recently, my friend (who was in on it) told him everything. Now he’s furious, saying I was vindictive and crossed the line. Even some of my own friends are saying I went too far.

But I don’t feel bad at all. He betrayed me in the worst way possible, and I made sure he never forgot it.

AITA?