I am disappointed that Hallie made such an accomplishment and the whole show seemed to revolve around what she did wrong. Your guest psychologist didn't even bring up the issue that people hate change and, knowingly or not, will try to drag a person, like Hallie, down so that her friends and family won't feel like failures themselves if they can get her to fail. Her mother, herself, said she felt like a failure when her daughter started loosing weight.
Maybe Hallie was over excited about her accomplishments and may have said some things that drove them away, but if they were real friends, they would have told her what she was doing or tolerated it like her boyfriend did.
I say Hooray Hallie!
As they say, you can't pick your family but you can pick your friends. I say if your friends and family cannot handle you succeeding, then make a new life with new friends and leave the rest behind. It will take time to get a new social circle but it can be done! I know, I've done it a couple of times.
Again, Hooray to Hallie!
Dave