I agree withggreg, you need to see a doctor now. Something is going on and you need to take care of it. Your esophogus can suffer lots of damage.
Well, bile backing up like that might indicate a gallstone perhaps or some other duct between the stomach and intestine is stopped up. And once in a while it has to do with the liver. Since this is something that has been going on for a while, there's no "quick fix." So, you'll have to go to your doctor, and he might refer you to a specialist. But it is not good to throw up like that, it will burn your esophogus, and it indicates something isn't working right at all, and it should most definitely be fixed soon. Sorry I can't narrow it down, but your doc will.