Yet another night left with the kids

My other half is trying all sorts of techniques to break my temper and make me give in. I’ve spent a long time over the last year not rising to it but its wearing me down. He doesnt get his own way he tries to provoke a reaction, he doesnt get that he silks. It’s been like this the last week I’m so worn out by it after a full day at work. He threatens to take money out of the joint, change his job , everything. I remain calm but I want to scream how did I end up like this ? The more I dont react the worse he gets. I had a whole summer of this then on and off now it’s back to full time I want to curl up and die if it wasnt for my wonderful kids. I’m trying to get evidence to apply for a non molestation order but it’s hard going.