Does he want us to sit in every night?
Yes. Because in his mind he owns you so you do as he says. If you go out, meet other people, build skills and gain confidence you might try harder to break free of his control. If he breaks your confidence (and the children's confidence) you will stay in your place underneath his foot.
To add to the weirdness I’ve got an invite to a prestigious do and he’s suggested we go to a fancy dinner. So that’s nice. Why am I not excited?
You were invited to something exciting and he's created alternative clashing plans to prevent you going? Well, that's standard coercive control. More abuse. Why can't you go to the event you were invited to? If he suddenly wants to go to a fancy dinner you can do that any night... Unless that was just something he came up with to stop you going to the event (in which case he won't be interested any more, or will ruin it, if you go to the event).
It’s often such a struggle to do stuff that I now give up before I start
When you go on the Freedom Programme you will meet other women who have been through the same thing because this is standard procedure in abuse - abusive men only outright "ban" you from things (like your course) as a last resort. In the first instance they are more subtle and just make it so difficult you give up without them having to ban you. So it takes you longer to realise they're controlling you. And result is the same though whichever method they use.
Last week's excuse was the presentation and you let him derail you and stayed home. Understandable - the idea it was deliberate and abusive was brand new. The possibility of defying him and his control was also new and I imagine scary.
This week he has found a new excuse (halloween) with the same goal: preventing you from attending a course that will improve your life and reduce his control over you.
I guarantee if you stay home this week telling yourself you'll try next week he will have found a new excuse by next week and then you'll rapidly reach a point where you've missed too much for there to be any point attending the final weeks of the course and you will have missed the whole course and have missed the opportunity and be stuck with him treating you like this.
The only other people living like this are women who are also being abused. People in healthy relationships with decent, non-abusive partners have totally different lives that don't make them feel exhausted and depressed because of the way they're forced to live by their partner's behaviour.
A decent partner would be encouraging you to complete this course and would be excited for you and thrilled to see you taking up such an opportunity and seeing your confidence grow. He would be making it as easy as possible for you to attend and be interested in hearing how it went when you came home. He would be building you up not breaking you down. (The way you did with your daughter and her activity.)
Have you got yourself a place on the Freedom Programme yet?