They are being vindictive. Because they are male they think it's a male trait. They want to be hurtful. They think the grass is greener on the other side of the fence.
Specifically how you define cheating?
depends on the situation , sometimes the only way is to cheat sometimes the worst way is to cheat .
Maybe because women cheat with them too ..... simple math !
No dumbo ..... Who are men cheating with ?
Something to do I guess.
Why do black light bulbs make it dark when you turn them on?