Well, considering damage against you is being DOUBLED, and the damage you are dealing is being HALVED...
of course Skyrim is irritating to play on Master, the difficulty that
requires you to exploit the game's mechanics because Bethesda doesn't actually put any effort into changing the difficulty.
I recommend getting Volendrung if you can yet. It hits hard like a 2H hammer but swings with the speed of sword. If you don't use restoration then use alchemy imo it's the only way to effectively heal yourself. If you do however I'd recommend putting perks to get the dual-handed efficiency one. That way it'll fill your high health pool faster and you wont need to carry an extra 1H sword to go with it.
It's better to dual-cast healing without the perk - Dual-casting increases magicka cost by 280% (As opposed to 200% for double-casting), but only increases output by 220% (As opposed to 200% for dual-casting).