Thanks for the quick reply. If you don't mind I'd like to further explain the situation. AFter I discovered her agoraphobia through some researching on the web, I called my brother in law to talk about it. He seemed somewhat defensive and explained how he tried to get her to get help but she didn't want any. He also told me that if anyone tried to intervene, he would block the attempt. Two months later when I called about holiday dinner, he said that he told her about the talk we had and now she does not want to speak to me. She's at the point where any mention of her illness might trigger a panic attack and he wants to avoid that at all costs. So my concern is what her condition will be in, let's say, ten years. My uncle told me he read that a possible end result could be suicide. Both my sister and her husband are VERY religious and do not socialize with other people much, if at all.
Sorry to hear that the usual treatment has not worked for you. I have a friend whose wife has agoraphobia and she has responded well to medication and counseling.