At My Birthday Party, the Nanny's Son Became the Protagonist

The day before my birthday, word spread that my wife, a lawyer, was going to hold a birthday party for me. But on my birthday, my wife who was supposed to pick me up suddenly broke the promise and said she was going on a business trip. She didn't tell me about the birthday party before, so I thought she wanted to give me a surprise. But why did you avoid me? What other husband does he have?