OP, having read all your posts, this is a tricky one.
On the one hand, working in a staff room is one of those work spaces where good friends are so helpful (according to my teacher friends).
But your gut is warning you and I am a great believer in that too.
I think him telling you he is heading off for trips leaving you with 3 young children is not on.
In my experience teachers really enjoy these trips and and there is no shortage of teachers who are game.
Often it is teacher friends who sign up for the trips, whilst pruning out any students that might be challenging!
I think the fact that he has gone to the spare room, is so furious with you, and has not spoken to you in four days, his pregnant wife, is extraordinary.
He is really very upset, isn't he.
I don't think you should be telling him who he talks to in work, but his reaction seems disproportionate.
Hard for him to argue that she is not a factor in your relationship if what you have said has caused him to move out of your bedroom and not spoken to you.
I think you need to sit down and talk to him, but I would be wary of him after such a reaction.
I think him TELLING you he is heading off on trips, which are holidays, is an extraordinary way to behave in a marriage with 3 children.
You were wrong in your response, but I can't blame you not being one bit impressed.