User blog comment:Omega natsu2/Episode 185: Erza vs. Kagura, Review./@comment-1359322-20140607031152/@comment-4449950-20140607031842

I was thinking about this too, but I came to a slightly different conclusion. I mean, I feel that in a way everyone was responsible: Jellal was brainwashed, but he wasn't strong enough to defy that control even to spare Erza and/or Simon. Erza was there, but she left the Tower and did nothing for many years to put a stop to what was going on - even just informing the authorities about Jellal and the Tower. She also failed to beat Jellal in battle earlier due to her weakness for him emotionally. Finally, Simon chose to step in front of Erza and take the hit, so that's there.

Now, I was looking back and thought about how everyone paid for this happening:
 * Simon paid with his life
 * Jellal paid temporarily with his sanity (suicidal), then with time in prison, then with his status as a criminal which means he's always on the run, then with his relationship with Erza (so far).
 * Erza paid... how?

I think this is how this part of the story was meant to be taken: Erza faces her repayment for what happened at the hands of Kagura.

Dunno, just a thought. There are many different ways to look at the situation and this is just one I've come up with.