In Doctor Sleep, a creepy ancient lady from overlook hotel is together with the black girl.
Why? What's the meaning of this? like she assumed the fears, and ghosts and is fine with them in her life?
The movie shows the struggles that Danny had, and the development and acceptance of her powers that Abra goes through.
Mrs. Massey, the ancient lady, is recognised as one of the strongest entities at the Overlook Hotel.
Danny, unable to confront her, works out how to box her away instead.
Why? What's the meaning of this?
It is a confrontation, the one that Danny could not do. Abra, however, is now older, stronger, and more in control of her 'shine'. She is now powerful enough to confront what was perceived as one of the most powerful poltergeists.
like she assumed the fears, and ghosts and is fine with them in her life?
Not so much this, but rather that she can deal with these entities in a way that Danny struggled to.
In the Wiki article for the movie:
" Abra later encounters Mrs. Massey, the ghost of the bathroom in the Overlook's Room 237, in her bathtub; she confronts it and closes the door behind her."