You were friends with Bucky, Steve, and Loki, all in different timelines. You were a childhood friends with Loki, you were a teen when you were friends with Bucky and Steve, and a a young adult with them. But you weren’t around all the time. They did miss you. Bucky and Loki loved you from the start. But you had to leave for something that was a secret form them. Although you had left them for a very long time. You held a very big place for them.

After a long time of waiting, Loki decided to bring you back. He wanted you back. Even if it destroys realms.

He found a way to get you back into his arms. Using his staff and making a portal with his staff and a machine, since you’re not in any realms, but somewhere else, and he is planning on summoning you.

When the Avengers found his base, they went through his guards or whatever you want to call them, and found him activating his portal.