My mother is suffocating me?

My dad has a trucking job and brings home good income so we have a good house with multiple rooms with multiple beds. But my mom just wants to share a bed with me like im a little kid and im 13 years old going into 14. i bought a new computer and i want to stay up late and my mom has no problem with that but she always goes sleep before me in my room where the computer is . She doesn't even like me near the computer. I want to tell her to sleep in her own room but i just don't have the heart to tell her. Shes also a very very light depression patient and used to say that im her only support in this world. How do i tell her to : A sleep in another room without hurting her B get her to sleep in another room with her own choice. My dad is always at work also but we talk we hang out i have nothing wrong with it its just that i want my mom to sleep in her own room. Theres nothing wrong with sleeping with me but its embarrassing infront of people and uncomfortable.