I'm convinced they buffed Malenia. I didn't have nearly this much trouble with her on my original character (STR build). I can avoid her anime attack pretty consistently now but the host of other quick attacks just gives her too much healing over time, and she wrecks me during the second phase. Her staggers and interrupts are also weirdly inconsistent. She heals too much off a summons for it to be of any use.
Oddly, I haven't had ONE coop partner in 20 or so tries live past her first phase so I don't know WTF is going on there. It doesn't really bother me or anything since I'm just trying her for 20-30 mins a night before buggering off to do something else; but I just can't really understand why I'm finding it so tough this time round. All the other bosses are dead. I'm using a STR/DEX build alternating between Dark Moon Blade and Moonveil with throwing in some spells when I feel like it. Curious.
Just started a FAITH/STR run through and I guess that will probably be it until DLC.