painful starters
"Loving you was a mistake."
"I hate you."
"You left me alone."
"There's nothing left to say."
"Was s/he better for you?"
"I'm sorry ---- I'm sorry I left you there."
"What do you mean, it's over?"
"Please don't say that."
"I can't forgive you."
"You turned your back on me!"
"You don't get to come back and try to win me again."
"I'm not giving a seconds change."
"What do you care if I die?"
"What do you care if I get hurt?"
"Who are you again?"
"This is over."
"I don't want to see you again."
"I can't do this. I can't see you anymore."
"I can't see you with her/him."
"I need to leave."