You're doing it wrong.
Try again.
Ditto. You svck at playing a mage. You HAVE to change tactics, which is a much more realistic expectation in a non-party RPG. You CAN NOT run into a room, turn a corner blindly, etc. There just is not enough time for you to react if you come face to face with a melee combatant. You have to plan your course of action, or react quickly. You can't rush or bulldoze. And yes, you may have to retreat and fight while backpedaling. You HAVE to, unlike the action-RPGs of late where mages are basically warriors with magic in place of swords and armor. They are, in effect, essentially the same characters. TES has never been this way really. If you play a mage, you MUST learn how to use your spells effectively. You CAN NOT rely on one spell 100% of the time (or even 50%). You can't even rely on ONLY one school. Mages are, truly, one of the most diversified characters you can play, and the most complex.
The character I am currently playing is a mage. He started as a mage and has never touched a weapon other than a very special dagger. He doesn't even use scrolls or staffs, pure magic. He's level 51, 100 in Enchanting, almost 100 in Conjuration, about 75 in Destruction and Alteration and Illusion, 50-60 in Restoration. Use no armor. Seriously. Work the perks. A holed-up studious mage wouldn't specialize in protecting himself from swords and such, but an adventuring mage would almost certainly invest in boosting those spell abilities. Perk mage armor, perk magic protection (both Alteration) and USE protective spells. Also, upgrade your spells. Buy new books when you can if you haven't found them. Perk your Atronachs since you're Conjuring. Let them enter the room. Cast them ahead of yourself as you stealth/hide. Dual-cast in major schools. And, above all, change tactics when yours are failing. It is entirely possible to take on an army of Forsworn and come out with nary a scratch. If you can't change your style, change your character.