For all the experience I have with this one I'm finding it hard to comment... Maybe because as bad as it hurts to stay it hurts worse to leave.
Of course I'm talking about the kind of relationship, therapeutic or otherwise, that is not healthy. On the other hand we'll sometimes run from healthy relationships for the same reasons we might stay in abusive ones. The hard thing can be telling the difference. The decision to stick it out or not is a very personal one...