This was in a conversation intended to make me understand our past squabbles a little because it has been bothering me for a while. It was late at night and over the phone (she'd refused to see me in person) so we were both rather tired. I was trying to explain to her how it upset me that she'd chosen people who had wronged her over me. The conversation was a little like this. 

She: Well, I think x is a very nice person.

Me: &lt;I was tired and this was sort of a reflex&gt; Hmm.

She: WHAT? GO ON!

Me: It doesn't matter.

She: Then don't say anything! If you're not going to follow it up then don't fucking say anything!

Me: I'm tired and it was an accident. I understand, I'm sorry.

She: Well you've got to say it now.

Me: Fine! It's just I know a lot about what x has done to people and I don't think x is a nice person at all, okay?

She then flipped out at me over my choice of words, being "I know a lot". She got really aggressive, mocked the way I said it, claimed it was unusual behaviour because I was just pretending to know a lot when I really don't. She then said it implies that I think I know more than her or that I have the full picture, which in both cases would be wrong, and it apparently also implies that I go around gathering info for the sake of condemning people like some sort of creep. According to her I've said this before without following it up with anything substantial and she finds it unnerving and annoying. 

I was really taken aback and a little hurt by what she said. It would have been easy to bite back, but instead I took a moment to catch my breath before responding calmly but sternly.

Me: I don't think I know more than you, though I might, nor do I think I have the full picture, I don't even think it's possible for anyone to. It's just that I do know a lot about this because my friends -- who have been hurt by this person -- have vented to me about it and I like to support my friends when they're hurt. I don't follow it up because being considered trustworthy comes with the responsibility of not spilling the stuff they tell me. I don't see the full picture, you're right, but I see enough of the pain they've caused to know that I think they're an arsehole and I want nothing to do with them. Is that reasonable?

She stammered for a moment before conceding that perhaps it was, but I can't help but feel that by having unintentionally provoked her I was the arsehole in this situation. Any idea? Thanks.