"how can one appropriately and succesfully oppose the borg in a way that helps people and doesn't reinforce the persecution complex?"
By exposing the WTBTS' false teachings... without utterly "shipwrecking" the person's faith in God, dear MS (and peace to you!). I have often marveled at how SO many come out with the belief that if/since the WTBTS isn't "it" (i.e., the truth)... then there is no "it." Who, though, besides them ever said they WERE? No one. Absolutely no one.
Not everyone ascribes to the belief that there is absolutely NO God. The teaching that there is no God is simply the opposite pole of folks like the WTBTS -and both are extremes. There IS a God, but He is NOTHING like the WTBTS teaches. Rather, he is exactly how CHRIST teaches... abundant in loving kindness, slow to anger, merciful... teachings which even unbelievers and aethists cannot find fault with. Unfortunately, most "christian" religions tend to follow the earthling man Paul (as he is sometimes revealed in his erroneous teachings and/or as they interpret him)... and so when the HUMAN "spirit" takes over... blame the Most Holy One of Israel.
The appropriate... and successful... way to oppose the Borg, therefore, is NOT to try and undermine the faith of those who believe in God. When you do THAT... you play RIGHT into their hands. Why? Because that is what they WARN people OF: if you leave us... you will leave God. And that is what many see - folks who leave God as a result of leaving the Borg. And THAT is why they stay IN.
It does NOT have to be that way, though. You can, instead, tell them the TRUTH... about the Truth. That there IS a way to serve God... NOT with fear and trembling... but with LOVE and truth and SPIRIT. And that it starts with only a mustard-seed of faith, and culminates in loving God... whom you have not seen... by NOT hating your brother, whom you HAVE seen.
Tell them the TRUTH, dear MS... and shame the Devil.
I bid you peace.
A slave of Christ,
SA