One former neighbour in the town of Gruenestrasse, where she lived with her parents before they split up last year, said: 'What a b***h for putting her parents through this.
'What sort of a person gives themselves over to a group killing her own people in Germany? I hope a jail cell awaits her when she returns, not yellow ribbons.'
School friends have described the quiet teenager as becoming increasingly withdrawn.
Another neighbour Angela Ehrenberg, 65, said: 'She was a very quiet, sensitive child. But there was an aura of loneliness about her that I could not understand.'
In 2015 she was confirmed into the local church. Female priest Maria Gruener said: 'She was a very placid girl who did not want to take part in confirmation instruction.'
But unbeknownst to her, Linda was falsely adopting the faith of the Christian church while secretly giving her heart to Islam.
As she attended the church, her parents' marriage broke down and she moved with her mother to Pulsnitz.
There, Katharina moved in with Thomas Weiss. Unhappy and insecure, Linda suddenly found herself with a new stepfather - and an older stepsister called Dana.
In May last year the troubled teenager made contact on the internet with an Islamist preacher in Hamburg who sent her a copy of the Koran.
'It seemed to offer her answers in a confused life,' said Christina, 16, a fellow pupil at the town's Ernst-Rierscher-Comprehensive school.
Linda (pictured before fleeing to Syria) used the counterfeit bank authorisation and her mother's forged identification papers to buy a plane ticket to Istanbul
'Last summer, shortly before we broke up, she began leaving home with a small bag in which she had an Islamic headscarf and long flowing robes which she donned to cover up all her skin. There were some arguments with staff.'
She stole her mother's credit card and secretly bought an airline ticket to Istanbul. Until six months before she fled she had never even travelled by train alone, it has been reported.
But on Friday July 1 last year she told her mother and father she was going to spend the weekend with a friend called Caroline and would be back in Sunday.
She never came home - and was never at her friend's.
Instead she travelled to Frankfurt and caught a plane to Istanbul before being smuggled into Syria.
Eventually, she ended up in Mosul where she changed her name to Umm Mariam, and was taken as a 'jihadist bride'.