i'm looking for the type where the girl falls in love with the boy and confesses and the boy accepts but the boy uses her and does something bad to her then tosses her aside then feels bad and finds out he actually likes her 😀 [m]

Skip Beat! begins like this.

Akatsuki no Yona does have a betrayal like this but his motivations are unclear.

The Girl From Class has this plot but it is the girl who uses/betrays.