Yeah people are unfortunately egotistical, selfish, and often petty. They try to get their way, sometimes even through manipulation. That’s what Niccolo Machiavelli observed as well, and then described it. One thing that has helped me is to keep in mind Marcus Aurelius’ quote of what he reminds himself in the morning.

“When you wake up in the morning, tell yourself: the people I deal with today will be meddling, ungrateful, arrogant, dishonest, jealous and surly. They are like this because they can’t tell good from evil. But I have seen the beauty of good, and the ugliness of evil, and have recognized that the wrongdoer has a nature related to my own.” — Marcus Aurelius

For Machiavelli, Marcus Aurelius was one of the Five Good Emperors of the Roman Empire, and a figure to look up to.