Ok, so I've never seen her wolf out except in the scripted underforge setting where you get the blood. Will she ever do it on her own in combat or is there any way to tell her how to do it? The bow is nice but it would be cool to see her tear into things.
I completed the game, and in all my time playing, and having her follow me, I have never seen her wolf out.
So, I guess not.
Normally, as said above, there is no way for her to turn werewolf...
But, if you are a PC player and don't mind a mod,
This may help, making her able to transform into werewolf and also the mod has some other helpful additions as well.