Angrboða

Angrboða, Loki's first wife, left him after what happened to their three children Fenrir, Jörmungandr, and Hel. The attacks on their children happened while Loki himself was out adventuring with Thor. By the time he returned, it was too late. The Asgardians had imprisoned his children. Angrboða had always viewed Loki as weak and cowardly, and when he tried to excuse why he did not or could not avenge their children, she left. He didn't blame her, but his resentment towards the gods was born.