Why me

I am 20 and I live at home my boyfriend and I have been together for a while now and we are thinking of moving out together. I talked to my parents about it today because they are always telling me how I need to move out and find a place, but when I told them they were so against it because him and I aren’t married?? I am upset because it feels like they are trying to control that part of my life but I am adult that wants to move out like they said I need to. Do I have the right to be upset ?? Do they have the right to keep me at home ?? I need help