But, she's not sending applications, she's sending group invites so blocking applications won't solve the problem. I'd ignore it. You could remind her that you don't agree with her and please to stop inviting you to these groups. Hopefully, she's a good enough friend to listen to you. But, don't join to debate politely. Most people on those groups have no desire to get into polite debates about the merits of different points of view. I know that's a broad generalization and assumption and I apologize for that. But, for every lovely polite person on those groups, there's more than one who will be rude.