Itachi lost a lot in his life. Having to kill his own clan was not something many could do with little to no after-effects. So of course he’s not going to let his precious little angel go.
Angel as in you. He just snatched you up and locked you up in his house and claimed, ‘It’s for your safety, Angel.’ Angel is what he calls you.
He doesn’t hurt you. He doesn’t abuse you, he doesn’t do anything like that. It’s more over mental manipulation, he’ll go on and on about how you can’t do anything without him even if you make the smallest mistake, treating you as if you are a helpless flower.
You aren’t completely in his control, He is still a soft-hearted man. If you are good the whole day, and ask him for something he will give it you. He loves you at the end of the day, And how can he resist that face?