Is Fidelity Antique

It's hard to watch the news or read a newspaper without encountering remarks about infidelity, either by a politician or eminent celebrities. Does it mean that everybody cheat on their spouses and why is it so common these days? Why fidelity seems an antique word, without meaning?
Years ago the betrayal was a taboo topic and affairs were condemned by society, breaking of the rules both by men and women meant disapproval and rejection. …