Nicolaou is right . This vaccine thing is overblown and it is not a core doctrine of the faith. Concentrate on Scriptural matters and beliefs . The slaughter of all but Witnesses at Armageddon is far more important and was a key thought in my awakening. Actually it is ok to express doubts, the Bible says so , Jude vs 23. I raised questions politely and humbly as part of my fade .. It takes time but it is possible to exit if you do it carefully.
Depending on their attitude the congregation can be easier to deal with than your family. You may have to compromise to keep family ties, that is your decision.