Sorry, I see how long you have been together and the house situation, and that there were drugs and rehab in the past.
"The house is a joint tenancy but I have been paying the rent. He says he is going but now he is sitting with a coffee."
I am afraid I do not know the ins and outs of tenancy etc, can you afford to continue to pay the rent alone. Once the dust has settled you can decide how to proceed.
"Do I really deserve to be treated like this just because I care if there's food in the house?"
Of course not, has this really come out of no where?
"I worry about money a lot because I'm an Accountant and I think I have just picked it up from my work."
You can work through this, if money is an issue, and things are tight you can budget and work your way out of it. If you are simply worrying without reason you can train yourself out of that.
Agree with AttilaTheMeerkat "He won't go quietly because he is getting what he wants out of this; he also has you to abuse."
You are paying rent and he can be mean to you, what kind of man wants to live like that? An abusive one.
Agree to contacting Womens Aid.
Also agree "... your boundaries in relationships are skewed and it may be that you've simply gone from one abusive relationship into another."
I wonder if he is jealous of you, "...all I ever do is my best, I work hard so we can have a decent life, I study so I can better myself and build us a future..."