Hey the borgs mind control techniques have been honed for 100+ years.
I was lucky enough to come out together but this is how I would handle it, it is how we have handled family and some are slowly forgetting we are tainted. (we are not DF'd just faded)
Treat her like an abuse victim - she is getting emotionally and mentally abused at every meeting.
My advice is to show her real love and real joy. Find things you can do together so she can feel that there is happiness separate from the borg. I know this can be difficult but if you have no "agenda".
Learn new things also, there are documentaries that are about other religions or history that might help her slowly realize also that you can do for fun instead of "here you need to see this". We were waking but watched a movie called Luther, I think it is youtube but that was really eye opening about the opposition Martin Luther faced.
Hope that helps.