Have you by any chance read Harper Lee's To Kill A Mockingbird, and the new sequel Go Set a Watchman? It's admittedly a series of sentimental, bourgeois apologist books, and the latter has a striking amount of apologia for racial segregation, but the central message is instructive.

You talk about members of your family "becoming" reactionary; you also talk about your mother being a TERF, which presumably means you always knew her to be a feminist of some sort. The "becoming" part also makes me think perhaps you at one time considered your family to be moderate to progressive?

In GSaW, Scout comes back to town long after the events in TKaM, and discovers that her father isn't quite the person she remembered him to be - not the liberal, headstrong lawyer fighting for minority rights we saw in the earlier book. I won't spoil the rest of the story, but truthfully, it's not worth reading unless you really liked TKaM (and thus need to be disabused of any Atticus Finch worship).

The moral, though, is that perhaps they're not "becoming" more reactionary; perhaps they always were reactionary - and Mao would agree. What you may have thought of as progressivism is likely bourgeois-Leftism, which is inherently reactionary. "...[E]very kind of thinking, without exception, is stamped with the brand of a class." (Quotations, p. 8, English 2d ed 1967).

One thing perhaps should make you take heart; these family members have been educated by a reactionary system, force-fed talking points by reactionary media, and have found scapegoats to blame for the ills that the system forces upon them. They don't live in a society with a socialist alternative. Neither did the peasants in backwater China prior to the Chinese Civil War, either. Yet, over time, and through education, Chairman Mao and the CCP were able to convert otherwise reactionary peasants into class-aware socialists.

As he said, "[t]hose with a 'Left' way of thinking magnify contradictions between ourselves and the enemy to such an extent that they take certain contradictions among the people for contradictions with the enemy and regard as counter-revolutionaries persons who are not counter-revolutionaries." (Quotations, pp. 49-50, English 2d ed 1967). Also "to criticize the people's shortcomings is truly necessary,...but in doing so we must truly take the stand of the people and speak out of whole-hearted eagerness to protect and educate them. To treat comrades like enemies is to go over to the stand of the enemy." (Quotations, p. 54, English 2d ed 1967).

So, in sum, do what I do - look at your family as victims of a reactionary system. Unless your family members are actively "taking up arms" for the reactionary cause, they're people who have been violated and indoctrinated. Would you blame the victim of any other crime for being bitter or otherwise affected?

Do your best to educate, but from a sympathetic stance.