Oi, so I'm on my first run through this game, I have a 31 Bosmer who heavily favors archery and conjuration in combat, and dual wields 2 ebony blades when needed.

Since the mid teens, I've been adding RP aspects to my style of play, which eventually has led me to wearing a black robe. I love the look on her and will stick with it for a while until I find something more suitable.

Any advice on how to adjust to losing so much D?

Most enemies still don't do much damage, but I still find myself in many near death moments, having when I need to depend on my close quarters tactics in caves and such.

Alteration could be your answer. You could use spells like Oakflesh/Ebonyflesh to raise your AR, this gives you an even better AR if you're wearing no armour. Magic resistance is also tremendously useful. But seems as your using Conjuration, stay away from Spell Absorption. You'll absorb your own summons.

http://images.uesp.net/c/c4/Fishystick.jpg

Lord Stone will give you a little boost. Lowering difficulty will allow you to survive more hits.