Boyfriend problems

So I have a 24 year old boyfriend and I'm 18. I'm about to pay for my own stuff because I'm graduating in a month... I'm hiding our relationship for now until it comes time but we "broke up". I don't know what the heck to do after gradation if I should wait another month when they know I can do what I want and need on my own or just not tell them at all because it's not their concerns anymore...  My mom is very angry at it and my dad is letting me do what I want after grad. But they said they will never accept me as their child again and take everything I have away from me or that they will never see me again stuff like that ETC. I just don't know what to. I want to move after graduation because I just don't want to be around them whenever it comes time to really live with him and be with him. I NEED HELP