I was listening to the stand-up comedy of Louis C.K. and at one point he is talking about his family and the stress it causes to be a father and husband and middle-aged. Despite all of the stresses though, he will always be there for them. He has been hardwired to take care of his wife and daughters.
He even remarks, how wonderful would it be if he could just wake up one day, not give a damn, and walk out. But he can't do it. He is just bound to these people and bound to take care of them (no matter how much he feels bound by them).
What is remarkable to me is the people he described. Some people are actually like that. Many people, actually, never do give a damn about their wife or girlfriend or children and leave them all, never to be seen again. It blows my mind that a concept that one person jokes about (because it is too horrible to ever consider seriously) is an absolute reality for other people, who even find it the best course of action.
This is a critically important point for storytellers. Many stories are works of fiction. Many stories based in truth still contain fictional material. We may consider them embellishments or exaggerations, but some of them are outright creations. However, just because something is absurd to you does not mean it is absurd to everybody.
Crazy, messed up shit happens in this world. Never forget that. Reality is scary and awful for some. And some people choose to make reality scary and awful. You can make up some characters who are thoroughly ridiculous. You can make them so incomprehensibly different and wrong that people may even tell you they are absurd and unrealistic. In all likelihood, there's somebody just like that out there.
Go and write your stories. Go and make your characters. Don't worry about whether they exist in real life. They do.