I had the same problem with my partner. He was so lazy, barely interacted with his children, barely lifted a finger with the house. Unlike your partner he was totally capable of housework. I threatened to leave him a fair few times, he would guilt trip me into taking him back. He'd be fine for a couple of weeks then he would go back to the way he was.
Then his mum became ill and he had to take care of her full time. So i let a lot of things slide. I think that situation made him grow-up a lot. Obviously you can't wait for something like that to happen.
I'm a stronger person now. He keeps throwing in snide comments to me like, how nothing had gotten done today, or how he doesn't want me to go back to work because the house would go to shit. He also reals things off to me that he wants me to do. I tell him to go to hell. This is my house. I'm the one who spends the most time in here. I'm the one who looks after it and the children that live here, if he doesn't like the job i'm doing then he knows where the door is. I don't take his shit any more and neither should you with your partner.
My partner does help out a lot more with the children now - except when it comes to sick or poo, but he has a really weak stomach and will throw up. I'm toilet training my dd at the moment and she did a poo on the potty, I was upstairs doing a puzzle with my ds and my partner went to deal with it. Next thing I know he's calling me downstairs to deal with it. I go. As I enter the downstairs toilet, he says 'I really have no idea how you do this'. It made me feel appreciated because after all that time of taking me for granted he was really starting to understand how hard my job is.
You need to find a way to make your partner realise just how special you really are to your family. You need to make him realise how the house and the family would just fall apart without you.
I don't have any friends much either by the way. I'm ok with that because by the time its time to go out for a night or something I'm always really tired and would prefer to stay in and read a book or have a bath or something. And during the day I find my days are so jam packed with the children and housework and errands I can never find time to have coffee with friends or anything. I'm where I want to be though and that makes me happy.
You need to kick his ass into gear though, seriously.
Good luck!