Why do rikki and Zane brake up?

ricci did it for zanes sake and he almost told there secret

Well, in season three, the three girls are helping Will reach eighty meters in diving. Will makes it and surfaces, as do the girls. The girls hide while Will swims up to the boat, just made a world record. Rikki, Cleo and Bella watche and Zane (Will's sponser ) yells out excitedly and kisses sophie ( will's brother). Rikki quickly swims away.
Then they go to the cafe. Zane approaches Rikki and tells her that she should have been there. Rikki says, " I was." Shocked Zane stares at her. Rikki then told him what she saw. Zane replied, saying that he and her got over-excited. Rikki doesn't believe it. She quits the cafe and ends her relationship.
Then Zane threatens he will reveal their secret to the world but he doesn't. He still has 'Feelings' for Rikki but Rikki doesn't want him back.