Portonys Complaint is not by Chaim Potak, its by Philip Roth
The reason I am shocked that so many frum people heard of the chosen is because many are not happy that the chassidish boy at the end becomes more modern and goes to college (The book never says he goes OTD from yiddishkeite, just doesnt want to be chassidish anymore) but I think for many it seems like he went OTD