I hate to tell you this, but by saying things like this, you are not much better than the authoritarians/totalitarians you seem to despise.
I do understand where the revulsion comes from, however. My own family, on my mother's side, during WW2, was reduced in size. Four out of every ten were liquidated by the occupying Nazis, and then two out of every ten (or one out of every three, if you adjust the denominator) were liquidated by the triumphant communists (to say nothing of battlefield deaths in-between, and the blanket dispossession that those left alive experienced).
That said, I do think that ideas and ideologies should be evaluated on their own merits, and should not be reactively shunned, because of an atrocity that happened generations ago. The reality, is that good ideas get hijacked and used by opportunists to benefit themselves at the expense of their neighbors. By being so vehemently against an _idea_, you create new opportunities for these kinds of pathological opportunists -- you create an entirely new category of scapegoats, whose pleas and screams and tears you can ignore, while they get dragged away, and separated from their homes and their families and their friends.
I'm not saying that you should cuddle up next to a communist, but I am saying that you should evaluate all people and communities in a nuanced and thoughtful way, befitting a member of _this_ community of absolute oddballs.