Mehstive

When you are completely indifferent or meh about something that is usually festive.

Person 1: "Christmas is coming up, I feel so festive!"
Person 2: "Meh. I'm not feeling it at all...I'm more mehstive."

Person1: "Someone has a birthday coming up, let's plan a festive get together!"
Person 2: "I am getting way too old, I'm not festive, just MEHstive."