Fab, things can be dumb AND fun.
It's all about reframing your mind and being emotionally and intellectually flexible.
Yes, when I look at Valentine's day from a detached point of view, it certainly seems dumb. But, if my girlfriend likes it and if that means I am assured of my nookie later in the night, who cares! I am every bit willing to dumb down. Being dumb often makes people happier. For example, dumb people derive pleasure from the simplest of things, blue sky, chirping of birds, cards, flowers, etc. They may not have the brains to derive pleasure from a chess match or a well-composed sonata or even a great philosophical novel, but hey, that's not their fault.
Again, it's all about constantly reframing your mind and being emotionally and intellectually flexible.