Why do you need a car? I haven't seen a university yet that allows students to have a car on campus the first two years. Public transit or a bike is just fine. You could move your horse close to the university then lease him out so you could still go see him. That way you keep him, he pays for himself but you can still go see him once in a while.
I've never been allowed to not work, so that is very odd to me. I have heard of it though but really don't see how it teaches responsibility and time management. I go to a community college full time, work 3 jobs at 55-60 hours a week and take care of my horse daily. I still have time to hang out with friends and do lots of other things. It can be done and many people do it everyday. Lots of us don't have a choice but to deal with it and make due. Also as Wallaby said, FAFSA is an excellent resource. You can at least apply and see what you can get in terms of aid and you don't have to take anything but the grants.