Nothing wrong with Spongebob humor. He has a lesson for everything, even if it's silly.
If you can't change it, embrace it. It's all about perspective. If you know you can't change how you feel on the outside, change how you feel on the inside.
I am an ugly person too, but I'm ugly and I'm proud. I joke with friends about my looks, I share my experiences with weight gain and weight loss, and I've even gone as far as tanning and waxing to make me feel "extra pretty" on the outside. I always compare myself to other girls and think "Why do guys fall for me and not them?" Because those guys appreciate who I am on the inside, not just looks. If you can't find what you like on the outside, find what you like on the inside and keep reminding yourself that looks aren't everything.