User blog comment:IamJakuhoRaikoben/Chapter 450: Alone in all the World, Review./@comment-3424593-20150831044341/@comment-9595671-20150831153122

Plus there was the fact that before Hades' actions in the Tenrou arc he was still appreciating life somewhat.

It seemed like he was on Tenrou Island where Mavis' spirit had been resting, hoping he could hold onto it. Unfortunately things didn't work out that way.

If its a curse of contradictions, the fact he no longer cares about life could explain this moment. When he cared he loved Mavis, so now that he doesn't care that means he probably no longer cares about that love.

Mavis still loves life though, somehow in a way when I look like this she's realized words won't stop Zeref anymore, and that the Zeref she knew is gone. So in a way she see might see this Zeref as if he was a different person.