How do you find out if your partner is cheating? Here’s a formula

A heartbroken man has come up with a witty and honest formula for how to know if your partner is cheating on you, to help other jilted lovers.

Guy Lucien wrote on question and answer site Quora that he discovered his ex-girlfriend was cheating on him when they lived together.

"I've always known that when cheating is occurring a few things happen and I'm not cynical but I'm a little skeptical," he said.

"I'm always being analytical of our situations. However with her a bunch of things lined up and you fellas please take notes - this is how I knew."

Here is Guy's formula for knowing if your partner is cheating:

He/she starts being less interested in sex

He/she starts being dismissive and forgetful

He/she starts always wants to know when you'll be home

He/she starts overusing their phone

He/she starts playing the blame game

Guy said as he started "being skeptical" he paid more attention to his ex's behavior.

"One day I purposely started a fight with her knowing she'd run away," he said.

"But I wanted to know where she would go . Sure enough we had a verbal altercation and she ran to him - I followed her car and waited for a few [moments].

"I called and asked where she was, she said she was at her mom's. Right then and there I knew she was cheating on me for sure ."