Keep it "Short, Sharp, and Sincere." Avoid a long debate; you are informing them of a decision, not negotiating.
Once the words are out, the conversation should end quickly to avoid circular arguments. dile que ya te cansaste, que algo mejor encontraste
When you feel lonely, remind yourself exactly why you were "tired" in the first place. Keep it "Short, Sharp, and Sincere
"I didn't come here to argue or revisit the past. My mind is made up." Keep it "Short