a habit - A habit is something you do so much you start to feel stupid

A habit is something you do so much you start to feel stupid if you don't do it.

I eat pizza every day. If I miss one day, my brain thinks I've been kidnapped.

I text my best friend 50 times a day. If I don't, I get anxious like I'm being haunted.

I check my phone every 3 minutes. If I don't, I feel like I've been exiled from the modern world.