Timothy you may lose your friend and that is sad. Unfortunately unless someone is in the right mental place to listen then it doesn't matter how smart or clear your points are they just don't take them in. They are distracted by the idea that you are walking away from the truth and will therefore die. They also can't contemplate that someone elses point of view might be valid.
She hasn't heard that you are happy, she hasn't heard that you are a person of faith she has only acknowledged that you do not share her faith. You do not fit the mould of ex JWs, miserable people who are making a mess of their lives desperate to get back but feeling unworthy to live up to Bible standards. As you do not follow the stereotype she can't process it.