My OH has a car (that FIL bought him and MIL pays the insurance on) and wants me to pay for petrol if he takes me anywhere in it. Bearing in mind the only time he really drives me anywhere is to the supermarket where I pay for all the food shopping and his fags and then back to the flat where I pay all the electric, gas and rent because he's on a zero hour contract and refuses to even try to get a better job. I was learning to drive before I fell pregnant and don't plan on getting a car until after I have our daughter. We got in a genuine argument over whether I should contribute to petrol or not. He doesn't ask his friends or his family to pay if they go out so why should I? AIBU?