Amy's advice can be divided into two parts. The first part, that LW shouldn't be so worried about being nice, bending over backwards for somebody who really is not as concerned about her feelings as she is for his, is correct.

The second, the script, is a bit stilted but probably effective.

The trouble is that LW isn't going to take any of it to heart. I can just see it now. They may nod along at the first part, but they won't really internalize it, and they'll never find a way to put this script into action for themselves nor modify it to something that they're willing to say.