I think that the goal is to not have just one person to rely on. In therapy, you're relying solely on the T and they are not relying on you at all. But if therapy is working correctly, you should start learning healthy interdependence, and also learn how to reach out to multiple people, not just one. And all your relationships become an exchange in both directions. Because no one is relying solely on one person, they can all share the burden of each other's problems effectively without tiring of each other or feeling smothered or overwhelmed.