feeling dead inside like a hollow husk

ive been going through alot to keep my fiance happy and every one else in my life hell ill even help someone random but i dont think of what i want or how i feel i just go out of my way for no reason at all. i noticed that slowly over time i forgot what it feels like to be myself and have the time to work on me and i just dont feel right like if you look on a closed box from the outside and it has nothing on the inside its a hollow object with thin walls that can be broken easily well thats how i feel physically, and how i feel mentally is like taking a usb or hard drive then wiping it clean like a blank slate, and emotionaly would be like fog that just dissapeared without a trace like it was never there. so is there anyone who can relate to how i guess you would say feel but lacking all actual feelings, ect.. and how do you cope or try to fix it?