
21M pure Nepali breed bull here living alone and fapping my cock in the garden hope nobody sees me wanking off like a pervert in the open.

21M pure Nepali breed bull here living alone and fapping my cock in the garden hope nobody sees me wanking off like a pervert in the open.
I'm 21M and I have a question, Why do guys want to cheat on their girlfriends and their healthy relationship? Like why? In my friend group all the guys are in a relationship they all have girlfriends except me but what intrigues me is why would they fuck around with other girl when they're in a relationship?
Here's an incident that happened recently to one of my friends he was in a serious relationship with his girlfriend of 4 years. A week before we and our friends went out to drink at a club that day he hooked up with another girl he met at the club. The day after that I heard him crying because his girlfriend broke up with him because his girlfriend's sister had actually seen him with another girl making out while she was with her boyfriend at the same hotel and she had snitched to her sister with a literal photo of them.
I had warned him not to do it but he didn't listen now he's crying and making a fuss. I asked him, why he cheated in the first place but he has no answer, just made excuses.
It's not just with him I've heard my other friends talking about taking and hooking up with other girls while being in a relationship.
What's the reason they cheat and ruin their own healthy relationship?