Alice committed suicide when Rufus sent her children to Baltimore and told her he sold them.
Alice leads a difficult life. She watched several children die young, and Rufus bought her and forced her into a wife relationship with him even though she was born free. Alice only consents to be with Rufus when he says he will beat her into submission until he does.
Alice’s father is a slave, and even though she was born free like her mother she ends up living a slave’s life. After Rufus sends her children away, Dana returns from the future and finds her hanging.
I stared at her not believing, not wanting to believe…I touched her and her flesh was cold and hard. (p. 248)
Alice definitely led a hard life, and she never managed to live a free life. When Rufus took her children, she finally found a way to get control of her life back--by ending it.
alice comited suicde because she thought rufus sold her children