short list of user stories for MVP:

as a user, I can sign up for an account.
as a user, I can login to my account. 
as a user, I can write an entry and send to the book therapist. 
as a user, I can receive recommendationsa bout books to read based on my sent entry. 

short list of user stories for your MVP:
screen for logging in / signing up
screen for writing and submitting an entry.
screen for viewing received recommendations.

user flows for each screen: