My perspective is very different because I've seen my parents (married 40 years and still in love when my Dad died). my grandparents and other relatives, and friends in my church who have been married over 60 years.
The thing is, though, the marriages were based on trust and respect and also loyalty. If you go back in time, infidelity used to be rare. And people weren't so narcisstic or focused on superficial crap. My father adored my mother and never cheated on her.
I did once have a friend who cheated on her husband. I told her she should either divorce him or stop cheating. We are no longer friends because I don't want people like that in my life.
And people aren't always out to screw each other. My husband and I unfortunately got divorced but we did not screw each other. He and I carefully split things so that it was fair to both of us. We did not even use a lawyer - our divorce cost less thatn $200. We both did the honorable thing.
I do think a pre-nup is wise since it protects both parties. It's like an insurance policy. You hope to never need it, but it's there if you do. I didn't have one, but if I ever get married again, I will.