I think with the clothing thing, she has worked out that shrouded in the black cover-all, she remains the jihadi bride figure. She's trying to look like a British girl.
I think she'll try anything to come back to the UK. I don't blame her. Any of us would do the same in her position.
I also know/have known of a LOT of idiotic, very silly, 15 year old girls. It isn't a rational age. They'll cut their noses off to spite their faces at that age. For the ones I've known, it has resulted in them being expelled from school. For a niece of mine, it involved being allowed to leave school to be homeschooled. Except she wasn't homeschooled and got barely any GCSEs. It's wrecked her whole life. No education. No career. Few work prospects. All because she was a stroppy teenager. SB didn't know what she was doing. And her life has been hell for the last 6 years.