You and Ron were only housemates and he didn't like you for yourself. He despises you. Then he found out he had to have a fake girlfriend to avoid getting Lavender to be with him since he also didn't like her, but he liked Hermione instead. Hermione is your friend but she didn't like Ron because she liked Krum. But you actually had feelings for Ron. He was forced into this and he sometimes hits you with objects like books, sometimes it left bruises or scars.