Beloved's Return

After reading the first 100 pages in Beloved, the main response I have is to Beloved. Does Sethe really not know who she is? Why has she returned? I wondered about the timing--perhaps since Paul D "got rid of the baby ghost," she found another way to be with Sethe. She says to Denver, "She is the one I need...She is the one I have to have," (89) referring to Sethe. Denver is hurt by this, as so far in this novel the main characterization of Denver is about her loneliness. She wants a friend and she wants attention. Denver wants Beloved to be hers and I wonder about Beloved's feelings for Denver. Does she feel resentful? She says of Sethe, "She left me behind" (89), both girls are conscious of the reason this happened, that Sethe was pregnant with Denver. SO far, Beloved does not seem spiteful, but as a ghost she was always causing destruction and letting her presence be known. Sethe says that the ghost is only sad, but perhaps we will see this develop as Beloved becomes stronger and more purposeful.
Her development does seem to be that of a baby's in ways, she is small and sickly, and initially incontinent (64), which might indicate the development of a small child. She also doesn't talk much and the phrases she forms are often puzzling or simple. Sethe also experiences a strange bladder episode upon first seeing Beloved. I'm not sure if this was to foreshadow Beloved's incontinence or to demonstrate some sort of connection between the two of them.
Ultimately, Beloved's character is the most interesting and mysterious and will no doubt be developed further. Hopefully we will get answers about why she is back at 124 soon.