How do you split your household bills?

I’m just curious on how others split bills and if I’m doing too much. Me and my partner live in Texas. I have a passive income of 2,600 a month and I’m a student and primary caregiver to 3 kids at the moment and he makes anywhere from 2,000 to 10,000 a month. Self employed and depending on the season. We have a son together and I have two daughters from a previous marriage. I own my house so I don’t have a mortgage. Just regular bills like electricity, water,food, car payment and everything the house needs to run and that adds up to about 4,000 a month. The way we split bills is I pay everything with my money and when he can he gives me 2k a month but there are months were he can only give 1k or less and some he tries to catch up to give me the 2k or more. But I do fall behind when he can’t give me the 2k that is needed for the house. I’m in school to earn more money because of that instability of his career. He insists that because I have two daughters he shouldn’t give me more that that but I feel like that’s not even a 50/50 split. Since I own the house we live in and I put in 100% of my income. He does pay his car and phone bill by himself. And I understand that but there has been months where he makes more than 20k and he’s contributed 2k. So with all that being said how do y’all split your bills?