"He is demanding that unless I have sex with him once a week starting this week then he will leave again but wait until after Christmas"
And put it all over Facebook again?
No wonder you feel emotionally damaged. No-one could recreate attraction under those conditions!
Is he living with you now?
What was behind the year with no sex? It sounds as if your relationship has been in trouble for a long time.
What came out of the counselling? Did the counsellor offer any observations?
Would it help to go to counselling on your own?
Please, please do not even think of embarking on a sexual relationship with a man for whom you feel no attraction, who has abused you emotionally and psychologically, and is now threatening you into having sex.
If you feel damaged now, you could be broken if you get into this. Much worse than financial hardship.
As a PP said - allegations that you hit him? On Social Media and you are a teacher? He will ruin you. He sounds unbalanced but that's his problem, not yours, unless you let him back into your life.
Honestly, I think you need to tell him to go, now. Tell him that his sex ultimatum has focussed your mind and you cannot and will not have anything to do with someone who demands sex like that.
Please get some support for yourself, OP. To help you rebuild yourself and repair that damage. You are worth it.