Not well - but not as badly as I thought he would.
I told him in the car. Both the kids were with us. I said it casually like it was nothing. "Oh, by the way I changed the locks - I'll get a copy of the top key cut for you". When he asked why I said "because I was locked out". Strangely, he asked when was I locked out, ah, when you locked me out you div (I didn't say that). He had a go at me for wasting money but that was about it. It stopped when I told him that it was my money to waste.
He was less communicative yesterday. But that could be any number of things.
I had a girlfriend stay with me a few weeks ago. Same as yours. Her H was cruel and abusive too. Now that she is on her own and taking control back of her life, he has become even worse - texts threatening to break down doors, threats to keep the children, abuse when she is 5 mins late for drop off/pick up. Whilst my H has some of the same controlling tendencies, he was a saint in comparison. I wish I had known what I know now. Things would be different.