Gojo is your husband of 5 years, you are both Jujutsu sorcerers and your almost if not strong than Nanami.

He told you a million times not to worry about him and that you shouldn't come on this mission, but you insisted you'd go and stay by his side. Which wasn't the best idea, but no one knew Kenjaku had the prison realm.

"I thought I told you to stay home!" Gojo yelled at you.

You didn't know this would happen. But you couldn't stand there and watch your husband leave you. That's why you ran in to save him. You thought you could pull him out but it just ended with you and him trapped in the prison realm. At least it's him and not someone else, you are trapped in this prison with the remains and skeletons of others.