Mister - the reason he is on full whack right now is because you are starting to assert boundaries.
This kind of acceleration in the behaviour you are asserting yourself against is called 'extinction burst' it is where the person demonstrating the undersirable behaviours feels their power to be in decline as the victim of the abuse starts to assert themselves and set boundaries.
The abusive person's behaviour will go far worse before it goes better (or goes away) as there is now a power struggle, you are no longer helpless and they feel insecure in the fact you are trying to stand up to them. They intensify the behaviours as a desperate attempt to reinstate their power in the relationship and get things back on their terms. If you keep to what you have said and stay strong in the face of this storm his behaviours will recede as they will have been proven to be ineffective against your boundaries. That is why it is called 'extinction burst' the intensified undesirable behaviour is like a 'last hurrah' of bad behaviour before the person finds new coping mechanisms as their abusive behaviours are no longer having you under their control! The behaviour is now extinct. They may have other attempts when they think you have softened in the future so never show weak boundaries again.
It is VITAL not to back down with your boundaries at this point or he will be victorious. Basically the last person to back down here will triumph and set the tone for how future interactions will go down - make sure that is you!!
For the sake of your emotional health and your sons - see this man for what he is a very damaged and dangerous individual projecting all his own pain and weakness onto you, but you don't own it - he does, it his HIS damage and pain to own and get help for.
You, however are strong within, you are a mother no less - you can do this for the time it will take to prevail, this is a huge battle prepare to win it and then you will be able to stand firm in any storm, you will know yourself and be able to figure out what you want and do not want in life and stand up for these! You have the strength in you for you and your ds and you need to use it now. Your strength is you love for your ds, you can and will do it for him, fight the emotional warfare and win - I did and you can.
Decide on boundaries that will improve your situation and stick to these for the love of your own well-being and your beautiful ds, there is far more at play here than the small victories themselves, you need to win each of these to win the war.
Practice saying things like 'no that won't be happening, I've already said so' and DO NOT LET IT HAPPEN!
Repeat like a parrot 'No I don't want to' and 'No you can't, we've had this conversation and you know why!' and importantly 'yes I hear that you want (whatever) but I have said .......(boundary) so that won't be happening'. Repeat repeat repeat ad infinitum - he will rage, get police each and every time you cant cope with his reactions.
Don't ask me how I know all this (long story) but I do know these techniques will save yourself, your son and your self-esteem ie everything you need for your future - these techniques are your way out of the mental prison so use them and run free from this abuse and the depressive illness it brings about!
I feel sure you CAN do this! I will be thinking of you!