Restoration (healing allies), Illusion (buffing allies), Alchemy (healing).

Perhaps my idea of a healer isn't so viable then. I forgot how lousy companions are in this game. That and they always take forever cause they go around the long way instead of just jumping.

Well, if you are a healer then they are supposed to get in the way of your healing spells, so that's good I guess

I don't have proper clip for that, but this old one should do as an example of combat with melee follower. Kharjo here is our one and only melee and I alternate between healing him and shooting bow (and running, because ancient dragon can killcam Raksha in one bite).
http://www.youtube.com/watch?v=13JLspM0FGo

Nowadays, I can go with 3 melee and its even more fun for me than this

Yeah. I'm just going to give up on this idea. It isn't as fun as it inititally sounded. I do not want to rely on companions, because I just remembered how awful they are!

For me I think the difficulty would come in actually remaining as a support role, I've conjured multiple atronachs infront of me, had a companion and her atronach infront of me and an enemy bandit chief has still decided to charge through every single one of them, ignoring them completely to power attack me despite the effort taken to get there.

Restoration
Block
Heavy or Light armour
One Handed - Mace (Enchanted with paralysis)

Get a damn good follower too.

I was about to say that at first how horrible idea it is being a healer in skyrim, but I decided to be more positive

Then be a pacifist.

Just paralyze all of your enemies.