Frasier - Season 11 Episode 2

Niles accuses Frasier of sabotaging his relationships whenever things start to get serious. Frasier vows to "commit to commitment," and tries to win Julia back. She accepts his apology and sleeps with him, and the pair seems to be getting along well. However, Julia proceeds to offend the entire Crane family during a dinner that Niles and Daphne had scheduled to announce her pregnancy. She even inadvertently spills the beans about the pregnancy (she overheard Niles and Daphne discussing it) before the couple can make the announcement. Frasier tries to excuse her behavior because of his new dedication to commitment, but ultimately dumps her.