I still have no idea what kills me half the time and am so sick of random 1 shots with a meta build.

I don't know exactly why you're dying, but I will tell you about my experiences. On my Lightning Spear Path finder I was experimenting with hybrid Armour Es. When I focused more on ES, I would have a fat health pool, but occasionally I would get deleted and not know why.

What I realized is sometimes I would face a mob, that either Did a huge physical hit with a bleed or a huge chaos hit plus some other big (physical usually) hit.

The physical hit would delete the energy shield and the bleed would delete the life. Or The chaos hit would delete the energy and the physical damage would delete the life. But when I focused more on armour, the physical hit would be reduced to a level that was manageable by my energy shield and life.

I suspect that you're getting to the level, where you'll need to go Chaos Inoculation. Or have some way to mitigate big physical hits with bleeds or poison components. Block might help, but I suspect you will still run into problems.

TLDR: You need a way to deal with bleeds and poisons especially those that are a result of large physical hits. The larger the physical hit, the stronger the bleed & poison. If you're depending solely on evasion and es, you will die and not know why.