So I have listened to quite a few of these podcasts now and I am starting to form a different viewpoint/theory on what could have happened.
SB was a young, naive teenager who already had her best friend in Syria who had joined IS. Her best friend, Sharmeena, initially did not want to travel to Syria alone and wanted all her friends to go with her. At this point, the other 3 girls said they were not going. Once Sharmeena was in Syria, she was telling SB that it was great out there and that she should come out to be with her. At this point, Sharmeena was still living in the Madafa alongside other unmarried women. By this point, she will likely have not seen what ISIS were capable of and the life that she would end up living. She managed to convince SB to join her and they were reunited in the Madafa.
All the girls were then married off as that was the ONLY way out of this Madafa and by this point, there was no way the girls could have decided to return to the UK as their passports and documents had been taken off them. Even if SB had made it to the Syria border, she would not have been able to travel anywhere. When SB was married off to Yago, he was essentially in charge. She had to obey him and what he said is what went whether SB liked it or not. It appeared she also lived with a very dangerous man who was an armourer for ISIS while Yago was in prison. She developed a loyalty to these people as she literally had no one else to turn to. You could perhaps compare it to Stockholm Syndrome where you form close alliances with the dangerous people in order to survive. I would imagine that if her husband told her to do something, like sew suicide vests, she had very little choice to do that otherwise she would have most likely been tortured in the Black Stadium or killed.
I think I am leaning more towards she was a naive, young girl who had no idea what she was getting herself into (how can you know unless you have experienced it?) and she was also trusting in her best friend telling her that it was a good life, which she probably believed herself at that point.
SB has been through trauma that most women could not comprehend and whilst I do not believe she should be allowed to come back to the UK and be a free woman, I do believe that she should come back and be tried here in the UK. However, I appreciate that there is perhaps a lot of intelligence information that would alter my view. I can only go on the information that is available to the public.