Is being miserable or unhappy in a relationship justification to cheat if the opportunity presents itself?

What if you're not married to the person? Is it still wrong to be unfaithful?
Update: My ex said that maube I couldn't trust him in our relationship because as he put it "Maybe you can't trust me, cause if I'm miserable and a woman shows interest, I might just take it". Then I discovered he had been texting a coworker of his hundreds of times a day before he left. He says he... show more My ex said that maube I couldn't trust him in our relationship because as he put it "Maybe you can't trust me, cause if I'm miserable and a woman shows interest, I might just take it". Then I discovered he had been texting a coworker of his hundreds of times a day before he left. He says he wasn't cheating but it looks suspicious. He's also using the excuse that we were fighting a lot and he was unhappy.

What do you think? Is it still wrong?
13 answers 13