The protagonist of this bildungsroman is Arthur "Artie" Kipps, an illegitimate orphan. In Book I ("The Making of Kipps") he is raised by his aged aunt and uncle who keep a little shop in New Romney, on the southern coast of Kent. He attends the Cavendish Academy ("a middle-class school," not a "boarding school") in Hastings, in East Sussex. "By inherent nature he had a sociable disposition," and befriends Sid Pornick, the neighbour's boy. Kipps falls in love with Sid's younger sister Ann, and Ann gives him half a sixpence as a token of their love when at the age of fourteen he is apprenticed to the Folkestone Drapery Bazaar, run by Mr. Shalford.
But the Pornicks move away and Kipps forgets Ann. He becomes infatuated with Helen Walshingham, who teaches a wood carving class on Thursday nights. When Chitterlow, an actor and aspiring playwright, meets Kipps by running into him with his bicycle, their encounter turns into an inebriated evening that leads to Kipps's being "swapped" (dismissed). But before he leaves Mr. Shalford's establishment, Chitterlow brings to his attention a newspaper advertisement that leads to an unsuspected inheritance for Kipps from his grandfather of a house and ÂŁ26,000.
In Book II ("Mr. Coote the Chaperon"), Kipps fails in his attempt to adapt to his new social class while living in Folkestone. By chance he meets a Mr. Coote, who undertakes his social education; this leads to renewed contact with Helen Walshingham, and they become engaged. But the process of bettering himself alienates Kipps more and more, especially since Helen has in view taking advantage of Kipps's fortune to establish herself and her brother in London society. Chance meetings with Sid and then Ann (now a house servant) lead to a decision to abandon social conventions (and his engagement to Helen) and marry his childhood sweetheart.
In Book III ("Kippses"), the attempt to find a suitable house for his new status precipitates Kipps back into a struggle with the "complex and difficult" English social system. Kipps and Ann quarrel. Then they learn that Helen's brother, a solicitor, has lost most of their fortune through speculation. This leads to a happier situation, however, when Kipps opens a branch of the Associated Booksellers' Trading Union (Limited) in Hythe, and they have a son. The success of Chitterlow's play, in which Kipps had invested ÂŁ2,000, restores their fortune, but they are content to remain, as at the beginning, shopkeepers in a small coastal town.

Question: Why did Kipps finally decided to end it with Hellen?
Answer: She was using and taking advantage of him.
Alternative answer: He meets Ann again