Hi Lunarlara,
Friendships within the JW are based on your interest in becoming a JW eventually. Are those the kind of friendships that are so conditional that you want to protect them. Yes JW can be so wonderfully nice and it can really draw people in when they are newly associated. But it is all an effort to get you to join them, it is less about you and how much they like on a truely friendly bases. When you show no interest in their religion they drop visiting quick enough.
Remember too as other have said you don't owe them any explaination for stopping your study. Just tell them that the JW religion is not for you it is that simple. You don't have to focus on anything, just tell them everything about it doesn't suit you. Your children will thank you for not leading the into that restrictive harsh religion. So many kids that has to deal with that religion suffer in ways you just could not imagine. Good for you researching the religion, we all wish that everyone would before getting involved in it.
Balsam