How can I stop this injustice from continuing to happen?
You can't. You have to suck it up, go along with it, and give the professor what she wants to hear.
Over my seven years of education, I dealt with a lot of professors who had a different world view than mine. The best ones graded me fairly for my thought process, rather than my viewpoint. Unfortunately, a number of them -- including the former President of the college I graduated from -- didn't grade fairly. At the end of the day, I got to speak my mind and stand on principle, but it didn't help my GPA much.
If you think this professor is going to grade you down for having a contrary viewpoint, your choices are 1) compromise your viewpoint, or 2) stick to your values, and risk the consequences.
If there's an anonymous evaluation at the end of the course, I'd fill it out. You could talk to the Department Head, or even the Dean, but you risk painting yourself as a problem child, especially if this is a respected professor.