Seeing her father again overwhelms the speaker. She says it felt like her lungs were collapsing, and the plain, physical way she puts it makes the pain feel real rather than polished. She couldn't hug him or tell him she missed him, so everything stays stuck inside her.
What comes out instead is anger. She wants to kick, scream, yell and cry, but underneath the rage is a child's longing: she wanted to tell him about her day and know he had been thinking of her. The questions "Why me" and "Why did you abandon me" read like something she has carried for a long time without an answer.
The ending is blunt and bitter. Trusting a parent with your whole life, she says, makes his betrayal cut deeper, and the crude final word shows how raw she still is. The mood is hurt, angry and unfinished, with love and resentment tangled together.