Hi @toodles
It sounds to me as if you have just had enough pretending you are okay when you are not. And your partner says he will just leave - he's not listening.
And your dissatisfaction is being blamed on your Mental Health. That's not good - we don't have to be mentally ill to be unhappy, unheard and just plain tired of the situation.
You have the right to leave - first - think about where you would go and if you can manage - there are shelters though I have no idea where to find them.
I wish I could help - I can hear you though - you need a fair deal and that's a fact - how you get it though - to say anything we need to know more - and it's up to you about how much you want to tell.
We all care here - welcome to the forum - and I wish you the best
Owlunar