Is it normal that i cant sleep alone??

Well.. Since I was young, i slept with my Granny or with my younger sis. Last 8 years back, I went abroad for studies.At first, I planned to stay in Single room but I am so scared to sleep alone ... I thought my fears might be gone as I grow older.....

I stayed in that hostel for almost 4 years , but I never became brave enough to sleep alone. I remember...one night, my roommate didn't come back to the room, I felt helpless, sweating , and I could not even breathe properly. I tried to sleep with the light's on but it didn't help. At last, I knocked to my neighbor's room , asked her whether I could sleep in her room for one night. It was really embarassing for me. It was not the only one night that I had to ask her help.Later on, my roommate moved to her bf's place . All the nights without her were the darkest nights for me.

Now,I'm 26, working and sharing the room with someone. It's a really big problem for me, since my roommate loves to talk online at nights . The whole day, I m so tired at work and I need a proper rest. But I am so scared to make the decision to move to single room. Is there any suggestion for me to cure my fears at night? Is it normal that I m scared to sleep alone ?