My daughter is now 3.5 years old. She is also sleeping either with my husband or myself. I have trained her for many many times, but still unsucessful. Actually this is my fault because I slept with her when she was a baby. Once she get used to sleep with me, it is very very difficult for her to sleep alone.
My friend told me that I need to trained her day by day and must not give up. Maybe one day she can sleep by herself.
I usually tell her story, and then chat something. Then I sleep beside her. When she is asleep, I get out of her room. I always switch on a bed light for her. But when she awake (normally at around 3:00 to 4:00am), she would run to my room and bring along her pillow and ask me sleep with her. It is happened in every day.
I had tried many many methods, such as stick a lot of stars in her room's ceiling, it can make her feel comfortable; say something encourage her (like "your friend she can sleep alone, she is a big girl how about you");she said she afraid of dark, then I buy her a bed light...etc.
I almost want to give up. :-|