For the nephew:
You have family that loves you now and will love you if you leave the JWs and the WTBTS. You have other family that will reject you if you leave. You are smart enough to measure the value of that kind of love. Think about the kind of parent that you want to be and make the hard decisions now, while you are young and you haven't twisted anyone elses future yet. Decide to truly love, unconditionally love. Your aunt and your cousin will support and love you either way, but unfortunately, are only allowed to be around you conditionally. That is a sad situation to bring a child into deliberately.
There are a lot of people that will offer support and encouragement, churches and community and faith groups that do not mock faith or God. The world is just like a kingdom hall in one way. It is good, bad, ugly, flawed, beautiful, challenging. . . .lots of good and bad and indifferent. You will be dealing with individual people for the rest of your life whether you are in or out of the organization. The thing is, most of "the world" is aware of its imperfection. JWs think they are "it, baby". They are just as flawed, but more in denial about it than any group of people I have ever known. They give lip service to being imperfect human beings, but find that their flaws are somehow more righteous than that of any other religion or group. That is a really obnoxious trait and JWs can't see that in themselves.
My best to you and your little one. Babies are truly a blessing from God and you will have a different view of the universe once yours is born.
M.