You are just going to have to live with the fact that you're the weirdo on this. People do not see Nazism and communism as similar or comparable. Nazism has discrimination and extermination of the "other" as core tenets of the ideology, communism is an economic model that simply does not have those elements no matter how desperate you are to assign them to it.
Authoritarianism is bad. But communism is not authoritarian. Governments calling themselves communist have become authoritarian and committed atrocities. But as much as weirdos like yourself like to deny it, governments capable of genocide are also capable of lying about being communist.