i believe her first love was her cousin, but he got a girlfriend (which didnt go well bc of his relationship with Lily), then later she fell for someone else who probably died;
which is why she believed that his death was her punishment for what happened to her cousin (the breakup and Lily "giving up" on him after that)
Actually Lily the one who died
First love was her cousin. He started seeing someone else but broke up because of his relationship with Lily. She was later confessed to by someone else, and that's when the cousin admitted his feelings to her (is how I read it). But I wonder if that was really love or just a feeling of not wanting to be separated from someone you care about (there is a difference)
I need some clarification when she was talking about her past love. Her first Love was her cousin and then somebody else, or was it the same person? Was it her feelings that changed or his?