Thank you all of you. This is everything I needed to hear.
Rightho.
I banged on about your boundaries upthread - but please don't despair, or imagine that this means there is anything fundamentally wrong with you. You might be amazed how many doughty old Vipers round these parts have tolerated, survived, then escaped abusive relationships.
You can too.
Because clearly your instincts are working ok, you are open to non-gaslighting points of view, & are thinking critically about your situation. These are all big positives - the only thing that's awry is that you lack the confidence to stand by your instincts.
Yet ... 
You'll get there.
The other stuff - yeah he moved in with me. Basically I paid for everything up until 6 months ago.
Fuck my old boots a cocklodger.
What a surprise. Not.
Whenever I’ve tried to say these things (above) upset me, he’d kick off. Say it was me. Play the victim. Categorically lie saying he hadn’t done any of them. I only know all these things because I found out. He’d deny, deflect, shout etc.
Shouting?
In your home? With your DC in it?
No no no no no.
Next time he raises his voice - tell him to leave.
If he refuses to leave - call the cops. I am not joking.
I had a big birthday. He bought me a badge. No cake. Didn’t sit and even eat lunch with me. He finds ‘occasions’ stressful etc blah blah.
Dysfunctional people always find other peoples occasions stressful.
Mainly because they are so busy sabotaging them, as they cannot stand somebody else to be in the limelight.
This is yet another classic technique of the abuser OP. Get yourself a copy of the Lundy Bancroft book linked above - it's time you sat yourself down & taught yourself more about this topic.
Started a fitness page. Targeted all the usual girls you’d expect on social media as that was his ‘business plan’.
Business plan my arse. Shagging spreadsheet, more like.
He was able to sit back "planning a business" because you were providing the roof over his head & paying his way.
Are you angry about that yet? You should be.
Last night when I tried to tell him how upset I was he said I was ‘relentless’ and I’m ‘fing constantly complaining’ and ‘always angry’.*
"Yeah I am. It's not me - it's you. You make me angry all the time, it;s time for you to go."
When you do finally brace yourself & sack him off btw OP - you do NOT need him to agree with your reasons. You don't need his acceptance, agreement, or permission. Keep it very short & very simple.
He is BOUND to push back. He won't want to lose his lovely cocklodging opportunity. So when you are ready - do you have friends who could be with you when you do it? Preferably, burly ones ...
This thread has honestly saved my sanity. Thank you all so much. Please go fully at the above and please feel free to go to town on me and what a class A plonker I am. I need to hear it.
You haven't been a plonker, you've been a loyal woman with a loving heart. Just to the wrong recipient. I wasted 19 years on what eventually morphed into my cocklodger. So you're already less of a plonker than me!
Please get single, & stay single til you've had some counselling & read up around dysfunction & abuse. You need to be stronger than you currently are, to navigate future relationships, & you will be, as soon as you dedicate a decent amount of time to proper self-care & education.
For example - if you'd known this when you first started dating the cocklodger, your alarm bells would have sounded & you would have ducked out when your recognised the Love Bombing, future faking, & demands for non-reciprocal exclusivity -
www.jennisspace.com/the-shark-cage-metaphor-spotting-potential-abusers/
Keep posting. Your instincts are sound, you just need to spend some time learning to trust them. & developing the assertiveness to act on them.
This man should not be around you, & should certainly not be around your children.