Am I wrong for this???

Okay so my boyfriend's daughter just left to spend the summer until August in Mississippi with her mother and with Father's day being tomorrow he's a little bummed and I understand because that they never traveled without each other.. So I want to still do something with him but he says he's not up for it because all the father's are going to be wished a " Happy Father's Day" and his daughter is gone.. I felt some type of way about that because after all I'm pregnant so I feel that's something he should still be happy about... Am I wrong for feeling this way????