During the attempt on Gaara's life, Yashamaru didn't just use physical weapons; he used psychological ones. When Gaara mortally wounded his masked attacker and realized it was his uncle, Yashamaru delivered a crushing confession:
The betrayal shattered Gaara’s mind, leading him to etch "love" (愛) on his forehead and vow to live only for himself. why did yashamaru try to kill gaara
Yashamaru intentionally shattered Gaara's worldview. Before this moment, Gaara believed he was loved and that his existence had meaning. By revealing his hatred and then blowing himself up in a suicide attack, Yashamaru ensured that Gaara would understand that the world was cruel, pushing him to adopt the philosophy that he needed to kill others to confirm his own existence. During the attempt on Gaara's life, Yashamaru didn't
Here is a breakdown of the reasons behind Yashamaru’s actions. Before this moment, Gaara believed he was loved
Yashamaru resented Gaara for his sister's death. He revealed to Gaara that he had never truly loved him; he had only acted as a caretaker out of obligation to his sister. He told Gaara that his mother had cursed the village and Gaara from her deathbed, and that Yashamaru had been waiting for the chance to avenge her.