Who told you that you have to be pretty, and why? Who sets the standard of beauty, and based on what principals?
I could say many things, but to keep it short, two quotes come to mind:
“You don’t need to be born pretty to be wildly attractive”
“You Don’t Have to Be Pretty. You don’t owe prettiness to anyone. Not to your boyfriend/spouse/partner, not to your co-workers, especially not to random men on the street. You don’t owe it to your mother, you don’t owe it to your children, you don’t owe it to civilization in general. Prettiness is not a rent you pay for occupying a space marked “female” – Dianna Vreeland