I totally agree. The slippery slope started when you could have sex purely for pleasure and without any consequences. While premarital sex may or may not be a "perversion," once that horse had bolted from the barn, the door was open for every other perversion under the sun to become normalized.
First it was "leave us alone in the privacy of our bedrooms." That, of course, quickly led to "we'll do whatever we want whenever and wherever we want." Which, in no time at all, morphed into "You MUST accept anything we do AND you must like it -- PRIDE!"
The other big factors were WW I and WW II. Women began working outside the home in huge numbers to feed the war machines which led to it being acceptable for kids to be raised without their biological parents present. Those wars irreparably changed our attitudes toward many things. Mark Steyn wrote in "America, Alone" that the wars ushered in nihilism and fatalism which made people not care about the future and their progeny. Fertility rates in many European countries dropped far below replacement, hence triggering the importation of ignorant third-world labor which is an unmitigated disaster.
Back then, most people were born, lived and died in the same city/county. The pickings for potential mates were few, and so you basically had to find someone "good enough" and stick with it. Of course increased mobility increased the number of potential mates, and now with the Internet, the illusion of "many fish in the sea", make it so that people hold out until they find their "soulmate", which of course in the vast majority of cases, never happens.
Pope Leo XIII had a vision some time around 1900 that the devil would have 100 years to destroy the catholic Church. Those 100 years are over.