What does it mean when she (Esperanza) says "the house I belong but do not belong to"?

Esperanza lives a life of true stories which she writes in her head. She tells the reader that "I am going to tell you a story about a girl who didn't want to belong" Esperanza again gives the summary of the family's different addresses, but she stops at Mango Street because she remembers the "sad red house, the house I belong but do not belong to" the most.

The painful emotions which Mango Street evokes in Esperanza are relieved when she finally expresses her love-hate relationship with the place upon paper. That is when "Mango says goodbye sometimes" at the moment, Mango is stronger than Esperanza, but she vows that "one day I will pack my bags of books and paper. One day I will say goodbye to Mango. I am too strong for her to keep me here forever" the final lines of the novel reveal Esperanza's true reason for wanting to move far away from Mango Street: so that one day she can come back for those- like so many of the characters we have met- who cannot make it out on their own.