Itachi was born to Mikoto and Fugaku, he was the older brother to Sasuke. He was incredibly close to his younger brother, to him, his life was worth more than anyone else’s. He didn’t have many friends, but like Madara, he did have one close friend, Uchiha Shisui. They were as close as brothers, and shared many ideas and views. However, certain events led to Shisui losing one eye, give the other to Itachi, then drown himself. His death caused Itachi’s Mangyeko to awaken. In the following years, he didn’t have any friends as close as Shisui, though he did make friends with Kisame. He did, however, make a good number of enemies, including Deidara and Orochimaru. Concerning betrayals, it actually Itachi doing the betrayal instead of being betrayed. Itachi betrayed his clan and his baby brother with the massacre.
Great Fireball Technique
Water Dragon Bullet Technique