Ex used to control me thru kids. Read about parallel parenting. Mine scared me for ages with threats of court years over divorce. I understand now he did it do he could control he and I had to do what he wanted or the threats would start.
I changed the dynamic and get none of that now. I set a strict schedule for visitation. No helping him out and bending over backwards anymore. He fits around us. I dmhave not spoken to him directly in years. Never will. All my text purely to tell him where and when to pick up our child. I am in control of schedule.
If he or his gf get unpleasant by text. I save them and ignore ignore.
I felt for years after I left he still controlled my actions and he contributes nothing positive to our kids. I am the responsible parent. I tell him nothing apart from what I want.
Only correspond reference kids. Hang up and block him of he starts. You have a right to live in peace. Set new lines and if he fights it and has a tantrum block him x