I also avoid soy
It is in EVERYTHING!
I also read that book by Jillian Michaels. No, she is not an endocrinologist, but that info was not coming from her. It was coming from the endocrinologists who supplied her the information and research for her book.
I was also told to stay away from soy by a couple of the endocrinologists I sought out earlier this year.
I think it is a personal choice. If you want to eat soy, go ahead. If you are not sure, then don't. There are plenty of foods out there from which to pick so it is not like you are limited. If you are vegetarian, then perhaps beans/lentils/legumes will be a good source of protein for you.