Will the marriage of a beautiful girl and an ugly looking guy sustain?On whose opinion are we basing the fact that she is pretty and he is "ugly?"
If she is thinking, "I'm pretty and he is ugly," I would say emphatically NO. She is shallow, unappreciative, and does not prioritize what is truly valuable in a partner.
If he is thinking, "She is beautiful and I am ugly," I would say MAYBE. He needs to understand that she values him for more than just his looks, and perhaps he is not giving himself enough credit (nor is he giving her the credit she deserves. Does he love a woman he thinks to be so superficial?) If he keeps such a low opinion of himself, eventually she will share it.
Matters of self-esteem and self-worth are devastating. Please do yourself a favor and seek help for this, either from friends or from a professional. You are worth it, and any thoughts to the contrary are only hurting you, the people who love you, and the people you love. My heart is with you xx