Complex sentence: The germ also forces the gas with the "death stench" out of her body, because of this, she began to think she was disgusting, that Tadashi wouldn't love her if she wasn't beautiful, and she would never be healed.
Split into simpler sentences: The germ also forces the gas with the "death stench" out of her body. Because of this, she began to think she was disgusting, that Tadashi wouldn't love her if she wasn't beautiful, and she would never be healed.