See tu (adjective), tú (pronoun), me (pronoun), bateaste (inflection of batting as "hitting with a bat to throw away").
TU ME BATEASTE literally means that you gave me a baseball bat, but in its colloquial and figurative form it means that they gave him pumpkins, or, as we say in Chile, that he kicked him, that is to say that he ended the relationship unilaterally.