Yes, at first she is. Took me a while warm to her. That said, it is fair to consider that we see things from Harry POV, a luxury Murphy does not have. I mean, we know Harry is doing his best to help and when he does not tell her things he has a valid reason (we may even disagree with his decision, but we understand there are logical reasons). Murphy does not know all that, she does not know Harry's intentions, loyalties and priorities. I see some of their relationship as quite alike to the classical Batman-Superman relationship in the comics. Batman is wary of Superman power and he took time to begin respecting Batman.