From the website: Those who wish to restore order and help the helpless will find him a strange but unwavering ally. Those who use their power for selfish reasons may never see Cole again—if they remember that he was there to begin with.
As for him attacking you, I think you'll have to make some fairly monstrous decisions. Something that poses a direct threat to something or someone Cole cares a great deal about (like what Kisari said about Rhys/Eva).
Pity, I do wish to restore Order but given the devs have now confirmed we can basically lead the Templar Order to war and victory against the Mages...
I'd expect his little buddy rhy's to be an enemy of mine.
To be honest i'm mixed on cole, glad he isn't walking around dressed as the Lord Seeker, i'm willing to give him some slack for that.
On the other hand, Demon.
But on the other hand, the PC has worked with demons in the last two games...
So it isn't easy, have to say though maybe i can convince him to go to the Fade himself, I'd like a non violent resolution if possible.
Assuming he proves his worth as an ally anyway, you don't grant respect to those who don't earn it after all.