human, are you asking why people who you consider to be radical (including yourself, perhaps) get called a variety of things by people who disagree with you? for example JZ used to call everyone he didn't like in the radical space a "leftist." and now he calls us nihilists, without ever defining his own terms (or only defining them in ways that are highly idiosyncratic).
you could argue that any "anti" anything is indeed reactionary. in fact it would be fair to say that anarchy (to the extent that it is about negating the state and capitalism, anyway) is reactionary. things that are anti-something are reacting to the something. the argument (i guess?) would be that there is a knee-jerk response to the something, rather than--for example--addressing the needs that brought the something into being in the first place, or accepting the reality of the something and making it be a positive somehow...
i'm perhaps not the best person to explain reactionary in some deeper, social way, since it's not a term i use or have had used on me (that i know of, anyway).
fascism is more complicated because it has more intense history, and a wide variety of international contexts that it is relevant to, from fairly empty name-calling to life-and-death struggles (like in greece). (if someone in the u.s. is calling someone else in the u.s. a fascist i'm highly suspicious... but maybe that's just me).
and liberalism is also a variety of things, from a fairly empty pejorative that means "reformist" or something, to something/one who is the opposite (on a single axis) of conservative (the definition of liberalism on wikipedia is good enough to help flesh that distinction out, i think).
but none of that has anything in particular to do with anarchy/ism, ie those are used as pejoratives by people (and against people) in a variety of political milieus.
if this is what you're asking, then i will make this post an answer. otherwise perhaps you can explain your question further?