Healers build for APOC2

I get stuck in APOC2 80K poison phase (I think its 5 power of dominance?)

My healers are: Laya, Elowyn, Carnelian and if you want to count it as healer so also Constance.

My Elowyn ult cycle fast enough so I can clear every other poison but my healers does not hold up and I die between the clearance of the position.

Another problem is the balance between attack and HP of my healers, they just dont survive. So I have to replace a lot of attack gear into HP gear.

My Elowyn build is left side: Astral Guardian. Right side: %atk, atk speed, rage regen invig set. She barely survive like this.

My question is how people who get to 120K+ build their healers? Their HP is really low but if you get them too low on attack they dont heal fast enough.