It's all about natural selection..
passing on of genes that really make a difference!..
people that mate for life are simply eroding the gene pool. The word "cheating" makes me cringe - as if to any extent anyone has the right to dictate the inevitable fact of evolution.
Anyone boring enough to demand fidelity should be automatically disqualified from the human reproductive process.
Being in any way threatened by any person's natural proclivity to mate is as good a reason as any to be sterilised!
To suggest that people mate for any other reason than a normal and natural response to human chemistry is to deny evolution and natural selection..
A fuck is a fuck for crying out loud - get over it!
For every woman that demands fidelity there are 1000 women who just wanna get laid - have a look five feet outside your precious self-absorbed outlook on life and get with the programme!
We'll all be dead soon enough, don't be naive enough to think that any one person's response to "fidelity" will ever change anything with regard to the propagation of the species - long after you and I are gone people will still procreate - and eat - shit - and eventually die. And guess which "side" of the species has control of this basic response to being born......