A new teaching pack designed to help teachers and pupils spot the signs of forced marriage is being launched in UK schools for the first time.
Children's charity, Plan UK, has produced an animated film.
It has different endings to try to highlight what happens to girls when they go missing.
The charity says hundreds of teenagers disappear close to, during or after school holidays to be married off in foreign countries.
It happened to this girl, who doesn't want to be identified.
"I decided to go on holiday to Pakistan and I went for about four months roughly," she said.
"While I was there I was told to enjoy my life, to let go and have a break from my studies for a while.
"I then came back from Pakistan and was just told I was engaged.
"One of my uncles called, which was soon to be my father-in-law and he said to me, 'I'm really, really proud that you're going to be in my family and congratulations. You're going to be my daughter-in-law.'
"That was the first I ever knew of my marriage taking place.
"I think it was easier for me, in my father's eyes, to suffer than his family suffer.
"He couldn't lose a whole family over his daughter and his honour would stay intact if I suffered, rather than looking at the prospect of losing his family and the community looking down on him."
After the relationship began to become physically abusive, she ran away from home with the help of a friend and her two children but says her family tracked her down at a refuge in London.
"They said, 'You either come back or we'll kill you and the person supporting you.'
"The way my parents tracked me down was through refuges.
"Unfortunately, what I didn't know, was that one of my aunties was situated in a similar area, so they'd actually got someone to follow me around."
The majority of cases involve families from South Asia, particularly Pakistan, India and Bangladesh.
Last year in the UK the Government's Forced Marriage Unit (FMU) dealt with 1,735 cases.
Marie Staunton, CEO of Plan UK, said: "This is the first national effort to provide materials for use in British classrooms on the issue of early and forced marriage.
"There are up to 8,000 cases of forced marriage reported in England alone.
"Overseas early and forced marriage is one of the biggest development challenges of our time."