Don't know how to handle this

I will start with some background. I am in college and work and have been with my boyfriend for 4 years and he goes to work and college alike. We both don't do drugs or drink and are very moral people. Anyways, we have lived together for about 3 years now and our relationship was pretty bad last year. This year I have matured more and so has he. We have been having a great past year and never had a fight or argument until now. So from what I have noticed is he will do anything his family tells him to do. Sometimes his family will say how much they don't like me and I told him to stick up for me because I try to be civil with them. His grandma uses money to bribe him and he always listens to his dad no matter what me and him have talked about. He will choose what they say over what we have talked about. Well today I told him we should sell his old car that runs like crap and have put so much money into ( a money pit ) and use tax money this year to get him a new car since he always drove my car because it ran good and had good gas milage. He agreed that it was a good idea and that he needed a better car to get around to school and save money on gas. Well when I got home he was talking to his dad and he's all " Yeah, you're right dad. " And I knew that they were up to something. I asked what they talked about and he said he's going to GIVE the car to his dad (who lives 30 miles away) so that his sisters can drive when they are old enough. Mind you this is a 1986 Camaro!! I asked him if his dad was buying the car and he said no..... I said that is not right. I used MY own money to help you fix the car JUST to get around. We have put 1500 into that car for repairs and you made ME drive that car in the snow when you had MY car for work. He said well my dad will keep it safe and I want it later on. I told him WE do NOT have the money to buy you a new car AND have another car with no profit earning for someone else to be using. Anyways he could not explain to me why... I don't know if they are up to something or what but I am so furious. We got into an argument and I really yelled at him which caused him to leave. He told me he doesn't want to be with me anymore ( I was calm with him at first trying to explain the smart way of doing it ) I even asked to compromise: Keep the Camaro and just use the taxes to pay off our credit cars. I don't know what to do or how I should feel/think. I'd really appreciate the advice because I don't have anyone else to ask. Thank you and I hope I get a response.

Kaela, the problem is that you have worked it out about the car between you and your BF, but he has worked it out with his father. He has cut you out of the picture. The fact that you have paid for his car to stay running in the past and you have let him use your better car while you drove his clunker, tells us the sort of person you are. Your BF and his family are on a different level to you..the whole lot of them. They have no respect for you and your input into your relationship with their son for the past 4 years.... and your BF has allowed it to continue to happen. Take your thoughts further and realise that your BF will always listen to his father and do whatever is best for his family and not you, because if you were in a relationship where trust, honesty and respect were flowing between two people, then your BF would at least acknowledge your input into solving the problem. Forget about morals, what about common decency? Instead, he has walked out on you after an argument because he can't see the forest for the trees. (immaturity at its best) If you state your relationship was pretty bad last year, then ask yourself what you need in a relationship..a mature man who 'walks beside you' or a 'teenager' who marches to his father's drumbeat?