If history makes you feel bad, that's fine.
We expect children to grow and, in time, to do without fairytales. Adults should be able to manage it, too.
There is no law that says a story must have two sides -- at least two, or only two. There is no law that says a story must have a hero to be true. No law that says: you must honour Columbus; or if you knock him down, raise up Las Casas instead. No law but the law of fairytales.
History does not care how you feel about the past. The past does not care how you feel about it, either. The past does not care what you name your schools, or your streets, or which mounted trinkets you set up in parks in honour of your feelings about it.
Galileo does not care that your colleagues dislike you or that your professor gave you a C-. He does not care that you are an atheist. He does not care about democracy or the idea that all opinions are valid on campus. He does not care that you think he went to jail.
The past is not at your service. It does not require your enjoyment, your understanding, or your consent. But to know where you are, *you* need to understand *it.* And for that, as perhaps for any real learning, you need to be willing to be discomfited.