Helda Hindi, who has returned to the Nineveh Plains with her parents and younger brother, spoke to Catholic charity Aid to Church in Need (ACN) about the night of 6th August 2014, when IS seized her home town.
She said: "Alarm bells rang out in our streets - we had to escape the living hell of violence and terrorism.
"I went along, crying, with no hope of ever returning to my town, my school - with no hope of ever seeing my friends again."
She added: "We had no idea how long we would be displaced from our beloved city.
"The days passed and we lived in torment and tragedy until we got used to it."
According to ACN, up to 44,000 Christians fled Helda's hometown of Qaraqosh, a Catholic majority town, when it was seized by the extremists.
The majority sought shelter in Erbil where ACN has supported churches building schools so that children could continue their education.
Helda said: "I was sad, clinging to hope of returning to my old school, but I made new friends.
"And today, by God's grace, we have returned to our town and I am back in my old school among my old friends."
The girl added that her faith had sustained her through difficult times.
"We had only God and we never stopped believing in His power and His mercy for all those hurting in Iraq and around the world," she said.
"My family, friends and relatives never felt that God was far away from us.
"As far as I can see into the past, God has been with me always.
"God is with me everywhere and I make sure to always keep nearby some pictures of Jesus Christ and a Bible."
Helda has pleaded for the international community to help others in her positions.
"My message to the West is to do as much as possible to support Christians in Iraq because they are close to extinction," she said.
"Help us. Have compassion. We want stability and peace."
ACN is working with the Nineveh Reconstruction Committee to rebuild Christian towns and villages in Iraq.
They have renovated 188 houses to date and are planning to renovate a further 554 homes in the towns of Qaraqosh and Bartella.
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