I had a feeling that Jesse was a bad'un when she came into it, but this really confirms it. I know we saw a glimpse of that earlier when we first find out that she knows Riley, but this was pretty harsh.
I feel sorry for Riley, she clearly likes John and doesn't want to be doing this. Maybe she's afraid that Jesse will send her back to the future. I hope she works it out and comes clean with John.
I presume when Jesse said "Your job is to keep him away from her" that she meant Cameron?? I remember one episode where she said that John was only talking to her, so does Cameron corrupt John or eventually have some hold over him?
I think Ellison is ultimately a good guy, however, Catherine has been able to manipulate his paternal instinct. I think that's what they were trying to convey there. He sees "John Henry" almost as a child. The child he never had with his wife. That's my take on it.