I am also what the Watchtower society refers to as an UBM who married a born in. Been married now for almost ten years and have been posting here for nearly four. I made a lot of mistakes, the biggest one is discussing doctrine. I guess I have been fortunate in some ways though as my wife was questioning many things about the religion before she decided to return to it so I have been gently working that angle over the years. I guess the only unfortunate thing for her is that her only two choices seem to be the witnesses or atheism even though I don't see things so black and white.
You need to school yourself on how cults work, some reading material that can be helpful is Combatting Cult Mind Control and Releasing the Bonds, both by Steven Hassan. Given my relationship with my wife and the other witnesses, I sometimes like to play games with them concerning their doctrines but I would not recommend you doing so, certainly not right now.
Teach your child how to think and reason past bullshit to ensure that he won't get sucked in to this or any other cult. I use to attend an Independent Fundamental Baptist church and they had some equally wonky and culty ideas.
Appeal to the authentic personality as much as you can, focus on things you two have in common and try to get her to enjoy her time with you when she is not at the hall. Spend time with your kid doing fun things, especially on meeting nights. She will eventually grow tired of attending the meetings all the time and want to spend time with you and your son.