Why do I die so quickly in legendary dragonplate armor with the lord stone?

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#1 Posted by Plasmabat (1675 posts) -

I am level 38 100 in smithing and all my weapons and armor are legendary and I have The Lord stone for extra protection and magic resistance, and 100 in heavy armor and have dragonplate and am 693 in damage resistance. I play on master and already beat the main quest, but bandit marauders take out half my health with a single lightning bolt and ancient dragons instantly kill me with their fire breath and their instant kill animation always plays after it has bitten me once. I also have 100 in two handed, but my daedric warhammer doesn't seem that powerful at 111 damage. Enemies still seem able to really hurt me. 

I don't have online so my game is unpatched btw.