If you can't afford both couples counselling and 1:1, then ditch the couples counselling. It is an exercise in grinding you down, all theatre, you are the villain, he is the hero. You don't need to pay money to see this drama - you have it in those notes and you know how he treats you.
You do need professional support though (as well as support and feedback from MN - I think it's a great resource) so use your money for that.
Wrt residency - this is his nuclear option, the spectre all controlling and abusive men use to frighten their victims into submission. As a wife and a Mother, I doubt there's much more terrifying in the world than fearing you could lose not only your marriage and your partner but also your DC. Yes indeed, and abusers know this, and they are willing to use the children as weapons against the mother.
If his weekends away involve money spent on accommodation, and if you have access to the account where the money comes from for all of that, then print out statements for however many years the pattern has been going on.
You can use any previous threads here as well as your own memories to compile a list of occasions when he has argued for decisions that weren't in the best interests of the children. You have the record of the antibiotics to back up your pov when it came to the skating. You don't even need that sort of solid backup for every single occasion.