Subject: Did I Overreact by Walking Out on My Fiancé After Hearing a Phone Call About Christmas Plans?

I (29F) have been in a relationship with my fiancé, Mark (34M), for the past two years. As Christmas approaches, I was filled with excitement about spending our first holiday together.

Just a week before the holiday, Mark informed me that he planned to celebrate with his daughter, Ella (6F), and his ex-wife, Jen, as they have done annually since their divorce. This revelation completely caught me off guard, as he had never mentioned this arrangement before.

On Christmas Eve, I overheard a conversation between Mark and Jen where he said, “She won’t know until it’s too late.” It became clear that he intended to stay at Jen’s house for the holiday, creating a “complete family” atmosphere without my presence.

Mark eventually confessed that they had concealed their plans because Jen felt uncomfortable with me being around. Feeling deeply hurt and betrayed, I decided to leave and spend the holiday with my sister instead.

Now, Mark accuses me of ruining Christmas for Ella and argues that I overreacted. Am I wrong for leaving after being excluded and lied to?