You shouldn't buy your ex expensive things.
Ron was a terrible husband and that's why his wife divorced him - now he feels bad about how he was with her.
Ron wants to apologize to his ex wife.
Ron calls his ex wife and convincingly apologizes to her for all the bad things he did to her.
Ron buys an expensive necklace to his ex wife and sends it to her with a heartfelt apology note.
Ron's ex wife believes he is sincere and feels vindicated.
Ron's ex wife feels he's trying to buy her forgiveness and feels used, once again.