Let's say this was not the JW belief system that is causing his behaviour change. Let's say, instead, that he was someone who had distanced himself from an abusive family. After marrying you and having a child with you, he decides he wants to give his abusive family an opportunity to be grandparents, aunts, uncles and cousins. He gives them a chance and starts to take on the abusive traits that he wanted to get away from so many years earlier, because he has more frequent and intimate contact with the abusers.
You don't accept the abusive behaviour, neither does your child. Your child wants you to divorce your husband because of the abuse. Neither you nor your child want to be subjected to the abuse any more.
When you think about it this way, does it make the decision easier?
Make no mistake, a JW who shows the kind of disdain your husband shows for you IS ABUSING YOU. It's psychological abuse. It's emotional abuse. You may not have bruises or broken bones, but you are being abused. The damage is being done, both to yourself and your child. And don't think that because there has not been physical abuse up till this point that there is no potential for the abuse to escalate into violence.
Start doing things to prepare for a separation. Open a 'secret' bank account and start putting money aside. If you don't work outside the home, start looking for a job so you'll be able to get housing. If you can, rent a storage locker and start moving your things there, or buying items that you and your daughter will need when you leave and store them there. Don't feel that you have to set up a perfect home - stick to absolute necessities for now. A few dishes, a few towels and linens, blankets, non-perishable food items, your documents (birth certificates, marriage certificates, financial records, drivers licence, passports, etc.) You can sleep on air mattresses or on a floor mat on a temporary basis, if worse comes to worse. Get a cheap pay-as-you go cell phone for yourself and your daughter with new phone numbers that your husband will not have for emergencies, or in the event that he cuts off your cell phone service. Start purchasing small denomination gift cards for grocery stores (or Walmart or Target where you can purchase almost anything you need) so you will have "cash" on hand in case you lose access to bank accounts or credit cards or need to be "untraceable". Prepare a "go bag" with essential clothing for yourself and your daughter, essential toiletries, medication, emergency cash and cell phone, and so on, in case you have to leave in a hurry, and keep it at a location your husband does not know about (such as a storage locker or at a friend's house - one your husband doesn't know and who won't disclose your whereabouts to anyone).