Dude. Let her go. She should be happy for you, not react like this. Enjoy your new car. You’re going to have plenty of dates in one of those.
If you are at a point financially or you can only buy a new car when the inheritance comes in then you’re also at a point where you shouldn’t be spending $42000 on a car. If your girlfriend doesn’t realize that then she is not financially responsible.
I’m sorry this happened, but…Be glad that she’s now an ex and find someone who won’t dump you after making an adult purchase for yourself. That’s insane!