Therapy and enabling

Is there a difference in therapy between enabling someone in their illness and changing their circumstances so they can cope? For an agoraphobe, it can hardly be said to be therapeutic to allow them to remain at home all the time, but to force them outside into their panic state as much as everyone else goes outside would be a wrong extreme too. You don't want to allow someone like that to fully withdraw from reality, but at the same time, you don't expect the same level of interaction from them that you would from others.

At some point you have to be able to say "That's enough for today", but how much is enough? I imagine it's hard for therapists to push their patients into uncomfortable situations and leave them there long enough to do some good, but not long enough to do permanent harm. But if you go too far in the "do no harm" direction, you're helping them stay sick.

Mokalus of Borg

PS - I'm not speaking from any personal experience.
PPS - On either side of the issue.