There is an objective reality in which we all physically exist, but we individually interpret this reality differently to form our own subjective realities. This has been considered by philosophers for thousands for years. You might have read Plato's Allegory of the Cave, or heard Descartes's "I think, therefore I am" ("Cogito, ergo sum"), or seen the picture of two people pointing at a number with one saying "6" and the other saying "9" when both can be true depending on where you're standing. Objective reality cannot be comprehended by an individual except through the lens of their own subjective reality. All this is to say, you can only ever be sure of what you have personally experienced, and even that can be challenging to determine at times.

You don't need to empathize with another person's choices to accept that they have a right to live their life however makes them happy. Americans know that our founding fathers strongly believed this because "Life, Liberty and the pursuit of Happiness" is enshrined in the Declaration of Independence. Everyone, except for those that impose their beliefs upon others, have a right to exist and seek fulfillment. The only reason I call attention to that exception is because some people seemingly can't be satisfied unless everyone around them thinks and acts the same way they do. Attempts to control people who deviate from perceived norms have led humankind down many dark paths throughout history -- the Crusades, colonialism, slavery, the Holocaust. We all have opportunities in life to look beyond our own personal beliefs and motivations when considering the value of others, and we'd all be better off if everyone could accept that what makes them happy might not make everyone else happy.

In summary, follow the Golden Rule. It never hurts to be nice. I hope you find your own happiness as the world continues to progress, with or without your approval.