A weirder kind of Deja Vu

Recently I was typing an email to somebody about a really unpleasant situation I had run into last week. As I explained how I had been verbally attacked by a woman I barely know, I had a moment of deja vu in which I suddenly remembered that my friend Becka had experienced that same thing about a year go and had told me about it. In fact, I remembered her telling me that she had had to take the same steps I was taking to defend herself from this person's venom. She had emailed, just as I was... I could remember her enthusiasm as she told me, and when I tried to remember the specifics of her situation, I happened to look up at the TV and something seemed familiar about what it was showing, and then the feeling faded. Suddenly, it was as if none of that memory of Becka had happened. I tried to recapture the memory, but it was simply nonexistent. Nothing like that had happened to Becka, not that she had ever told me anyway. The entire "memory" had been a deja vu.

I was mystified. Deja vu normally makes present events seem like they have already taken place for you, not for somebody else.