What he 'knows' is none of his business! FWIW, all idiots like this accuse us of cheating when we start to wriggle free of them. They sense our strength and as they lloathe us so much think it inconceivable that the strength is ours alone, so we must be seeing someone.
The us leaving them is also their worst fear. What they fear most, what they insult us with, are the insults that'd hurt THEM most. When I had this from my ex, me turning the insults around, absolutely floored him, I was astonished!
If he threatens you, call the police.
It really is that simple. Please let the law deal with him. Don't invest a single second of worry over him. Please. He really isn't worth the headspace.
You are entitled to end a relationship for any reason. He has made this relationship impossible, and completely unviable. You are entitled to be left alone if that's what you want.
When you get away from him, Don't let him have direct contact with you, change email address, change numbers, and if you think he's got some tracking thing on your phone, ditch that too.
Can you get an IT person to clean your PC?
Fight back chick, and this guy has no right to do any of this to you. Disengage.
Oh, and making you give the heel of the bread to your child is ridiculous, most people chuck away the crusts.
If he's so precious about bread, tell him not to bother to make it, as it's not worth the aggro over what others actually bin!
Be strong love, once he's away from you, it'll all get easier.