Here's my two cents:
About male's nature nga mag cheat, i partly agree. We use this context differently for family and among friends. If sa family, obviously, we are protective about it and using the " its the male's nature " excuse wont work. Using it is not proper. Unlike group of friends, we use this context to comfort our friend, we can't just tell them to go chase after the guy and kill him and Im not sure if your friends are willing to go on commit crime and kill that guy for you. This is my opinion though.
So why do men cheat?
1. Boredom - even if naa ka gf, some gf just aint that active. Dili pro-active sa mga activities.
2. Choke - sometimes, guys just needs a break, and they don't want to tell their gf about how they feel because their gf might not understand it.
3. Easy to get - we couldn't just blame the guys all the time. I myself would agree that if the new party is easy to get, we guys tend to lean and say...." Why not try it out? - easy come, easy go "
4. Opportunity - If we guys aren't given opportunity to cheat, would we risk it? I won't.... unless if everything is laid infront of you, without any hassle and all.... " Let's jump in... "
5. I didnt find this in you - This is common excuse, i dont think i need to expaund on this.
6. Challenging - some guys just like challenges.
7. Psychological - some guys got hurt by their exs, and they want revenge.
Overall, Cheating is just wrong no matter what the reason.