我怕黑你是光却照亮了她
[wŏ pà hēi nĭ shì guāng què zhào liàng le tā]
I am afraid of the dark and you are the light, but instead of shining on me, you illuminate someone else. This expresses feelings of sadness, loneliness, and envy because the person's love interest is focusing on another person rather than them.