Defenses in this game just sucks...this isn't it GGG

So all throughout my playtime in this game leading up to this point I probably swapped all my equipment and passive tree around so many times I can't remember where I started but somehow my defenses just feel worse going into endgame. No matter how great my equipment rolls and no matter what I grab on the tree it seems to do nothing making the passive tree kind of pointless in my opinion. POE 1 tree at least made it that if you invested in defenses you can at least make it through most maps with little problems at the cost of DPS but this is just insufferable to say the least. Why do white monsters with slam skills 2 hit me? They are even lower level than I am and the stun locking is so annoying when it is back to back. I can do here and there but some of the skills the monsters have just seem overtuned. Rare monsters are easier to me than some of these packs of white monsters which is just weird...