The apparent lack of familial issues was merely an illusion. As soon as divorce became a realistic option the numbers of broken homes exploded as victimized women fled abusive relationships.
Much of the troubles among minority communities, especially African Americans, came with the war on drugs. That single policy has systematically destroyed entire generations, and not by accident.
The internet and modern 24 hour cycle media can be thanked for the impression that we're more stressed and divided than ever. Crime has actually been in a steady decline practically since our country started tracking those statistics. When something horrific does occur you can be sure that it'll be published and covered to some extent by dozens of news sources. Major political divisions have been with us since the founding of the country, the only real difference today is the speed and omnipresence of the media coverage today.
Wealth inequality has definitely been getting worse, which is why the middle class is disappearing. Obesity has risen as access to food has increased and sedentary lifestyles made more of the norm. Despite both of those things though the average person today likely has access to better healthcare, at least on the medication side of things, and a longer life expectancy.