I'm currently in the process of leaving.
My partner did not tell me about his recurring depression until a few years into the relationship & I had moved in, away from my support network. It only came out because he was starting to get depressed & his behaviour was affected. I would never have moved away from my support network had I known.
But I had committed to the relationship & decided to continue; we went in to have 2DC and my life became hellish.
He had multiple job losses, long periods off sick & it put us under extreme financial stress.
I was out working more or less full-time & doing everything round the house. He just didn't pull his weight at home & I was buckling under the strain.
When he finally lost his job, for mental health reasons, he got more treatment & felt better. Then he sat round the house doing fuck all whilst I worked full-time.
The resentment killed my feelings for him.
I should add that he always tried to help himself with therapy, medication & exercise. But he just couldn't see beyond himself & support me at all.
I realised I couldn't go through life propping up someone who didn't support me at all. Imagine going through to old age in that situation. It's supposed to be a partnership.
I didn't want my kids growing up thinking that this was how relationships work - with daddy doing fuck all & mummy running around shitless trying to do everything.
In some ways, I wish I had done it when the DC were young enough not to be as much affected as they are now (11 & 7).
Good luck OP, it's really hard.