What happens at the end of tempted house of night?

"He catches Professor Loren Blake and her after they had sex with another."

this is incorrect. he never broke up with her for that since at the time they werent dating. in tempted Zoey broke up with Erik because Erick was becoming possessive and controlling and she was tired of having to answer to him for every little thing. so she told him to leave unless he was willing to change and he wasnt so he left.