You are right - this is emotional abuse. There is nothing ok or normal about it. You are depressed and it's because of your awful relationship and living situation. Its entirely understandable that you feel suffocated, despairing and desperate.
There is a way out though - as scary as it feels, as impossible as it seems, you can get out of this life and build yourself a new one.
First step - go back to the gp (a different one if you can) and say you're depressed and you are in an emotionally abusive relationship. Be clear that you need help. Take the anti-depressants you will be offered - they will help you to get to a mental state that will allow you to plan carefully.
Once you feel ready, call women's aid and/or any other resource www.womensaid.org.uk/information-support/useful-links/ you can find. Find out your rights in terms of your housing situation and getting him out and also start researching benefits etc.
Make sure you're being careful with your internet history. Make sure you've got all important documents (passports, birth certs etc) stored in a safe place.
Start telling people - begin with the couple of friends and family member you mentioned in your first post, the ones who aren't taken in by his nice guy act.
The most important thing right now is to get yourself into a mental place where you can do all of the above. Take each step as slowly as you need to but hold onto the thought that you have a new life waiting for you and your DC.
My final point - your DC will notice a lot more than you think they do. They are watching your relationship and absorbing how it is as the way it should be for them. Any upheaval for them is minor in comparison to the impact this is having on them.
We are here for virtual handholds. You can do this. You deserve a life that let's you breathe easily and isn't full of anxiety.