To dream of your car broken into usually means that you feel as if you have been violated. Many people see their cars as being extensions of them. They think that if their car is being broken into, that someone has just seen them at their very core and has formed judgments about them. Even if nothing is taken from the car, the mere fact that it was broken into brings a feeling of powerlessness along with it. If only you had been there, you could have prevented it. If only you had done one thing differently you wouldn't have been in this situation, if only you had parked across the street instead of right in front of the store. The list of if onlys goes on a long way and ends nowhere. You can't keep telling yourself if only this, if only that all day long. It will do you no good and only serve to make you feel worse about it. This is what would happen if your car were actually broken into.
When it happens in a dream though, this means you are probably asking these same questions of yourself only for a different reason. Perhaps you have done something which you knew you shouldn't have done and it leads to an undesired result for yourself. Even more likely, something happened that was totally out of your control and it lead to an undesired result for you, and now you are feeling the aftereffects of this violation. You wish that you had done so many things differently. And if this line of thought is leading to bad dreams then it is probably leading to you getting all sick to your stomach over nothing. Even if what happened was truly an egregious violation of yourself as a person, it is too late to be thinking about what you should have done differently. You can't afford the luxury. What you have to do, as much as you might not want to hear this, is suck it up and move on. It is your only recourse when something like this occurs and it is all you can do in order to help yourself.
When you dream that your car has been broken into it is because you feel like you have been violated. This is the only answer to a dream like this, (unless it really is a deep seated fear that you have of your physical car being broken into). If you are not sure if this is true for you, then you might just be trying to suppress your feelings. Try going over your feelings a bit more and see what conclusion you come to. You could realize some startling insights once you start to think more about it. The only help for you is if you relax, settle down, and move on from whatever happened, once you realize what it is.
Having your car broken into can in some cases be worse than having your car stolen from you depending on what is taken. This is because it can lead to an even greater feeling of violation. You probably feel like you have gone through a massive personal violation but you just have to remember that time will heal all wounds.