Seperating need advice?

Husband & I are seperating he's moving into rented which he can't afford but won't go back to his mum's cause he can't stand living under her roof he say's!! Anyhow he's agreed until our house is sold to pay half mortgage/utility bills but said he can't pay anything towards the kids we'll both just need to be skint until the house is sold. He would be left with money plus he does small cash jobs so would manage to give me something as he earns alot more than me and he has choosen to move into a plush flat instead of thinking about being able to pay money for the kids he said he's going to need to keep a float to pay his own place plus half our home. I'm not happy as the kids need to be fed, clothed and kept amused for the next 3 months of holidays am I being unfair????