Thankyou for the advice.
An example of the things he's done that have made my mental health worse are:
Sexting a co worker after our first baby was born around 6 weeks old and then lied to me when he said he stopped talking to her. (I also just got diagnosed with pnd so blamed myself and was scared to leave)
Telling me my panic attacks and anxiety about him cheating and leaving were stupid and ridiculous.
Keeping sexual pictures of other women off websites on his phone while I was pregnant with our third as I wasn't giving him enough "sexually" and telling me not make a big deal.
He plays video games constantly, either on his phone or various consoles I do everything unless I ask him too, which he then causes a fuss about. He works full time I'm recently self employed, he works roughly 5am - 3pm and sleeps at least 9 hours a night roughly, I get up with all the children in the night always have, I cook, clean, make sure he has clean clothes and a cup of tea ready for when he gets home from work he will get in and play his games until he goes to bed, he plays with the children and will do a good job to look after them if I'm not here but even they have noticed how often he plays his games.
Every argument I get accused of being crazy and it's always my fault we argue, if I was "Normal" they wouldn't happen, he belittles me in arguments and makes my feelings feel invalid.
I'm not allowed to be stressed or miserable dealing with a mental illness and four young kids but he's allowed to be miserable or stressed or tired.
Recently I was told I'm lazy untidy and my children will give up on me because I'm such hard work with my depression and anxiety.
I do everything for him and the children and I feel I'm not appreciated or supported at all. He will then turn around and say he loves me and can't be without me so my head gets very confused.
I'm so unhappy but I feel guilty for wanting to leave especially now his mum has cancer and feel like I'm responsible for his happiness and I'm a bad person for even considering leaving but I just want to be happy.