Today, there are more women serving in and returning from the war zones of Iraq and Afghanistan than have ever before served on a US battle front.

Although it has not been specifically mandated, more women have become directly involved in frontline combat over the course of the last decade.

This new reality for the US military and the women who serve in it has resulted in a host of issues that are challenging the government organisations that are supposed to serve them as veterans.

In the past 10 years, the number of women veterans facing issues related to Post-Traumatic Stress Disorder (PTSD) - such as substance abuse, depression and joblessness - has more than doubled, while the number who are homeless is estimated to be over 15,000 nationwide.

It has only been within the last few years that the Department of Veterans Affairs (the "VA" is the primary US veterans' health care organisation) has recognised the seriousness of PTSD among women veterans.

One leading independent veterans organisation recently addressed this issue at their national convention.

"Female veterans have their own set of problems," notes American Legion National Veterans Affairs and Rehabilitation Commission director Verna Jones. "They want to be recognised for the service we provided for our country.

"Though some women veterans who come back may not have outside physical wounds, they have those invisible wounds of war that they have to get through. So many women veterans won't tell about the traumatic experiences that cause them to have PTSD."

In January 2011, the American Legion conducted the first female veterans' survey since 1985. More than 3,000 women vets responded.

"What veteran women want is quality health care, affordable medications, and ... equitable compensation just like their male counterparts," explains Jones, who says the results of the survey inspired a new outreach programme to support female veterans and "help guide them through the VA system".

Making this film was truly a journey of inspiration, trepidation and, ultimately, unexpected joy.

I had heard about the situation of female veterans returning from Afghanistan and Iraq with PTSD, and wanted to find out more.

After a long search for somebody who was willing to come forward to share their story, Operation Stand Down Nashville - the Nashville branch of a non-profit organisation that helps veterans transition back into civilian life - put me in touch with a veteran called Lindsey.

It was a fellow filmmaker, Patricia Foulkrod, who first introduced me to Mary Ross at Operation Stand Down and from the first time I heard Mary's southern drawl and infectious laugh, I knew she would be part of the story I wanted to tell.

Mary felt that it would aid Lindsey's healing process if she was to open up and share her story, but when I first met Lindsey she seemed visibly shell-shocked.

Even though she had been out of the service for more than three years, she was still suffering from PTSD - unresponsive, self-effacing, struggling to put entire sentences together and really not too sure about participating in the film.

It took us driving around together, telling stories and sharing a good southern meal of hush puppies and fried catfish before she started to slowly let me in.

Because of Lindsey's vulnerability, this was perhaps one of the most difficult films I have directed to date. Up until the very end of our 10 days with her, I was not sure if we would have enough material for a film. I was also questioning the entire process of making the film and whether Lindsey would be further damaged as a result of speaking publically about her ordeal.

In essence, this is a story about two generations of women who served in the US military, seen through one young woman's struggle after two tours in Iraq. It is also the story of how two generations of women who fought in two different wars have come together to pursue accountability over the shortfall in health and human services provided to many female vets.

There are chapters of Operation Stand Down in almost every city but the one in Nashville is quite impressive, offering housing, counselling, job training and placement among other things on a full-time basis. Mary and her colleagues are tireless in their efforts.

While the overall number of homeless veterans is steadily declining, Mary says the percentage of women among them is definitely on the rise. This unprecedented number of homeless female veterans raises questions, including whether there is gendered homelessness or gender-specific reasons for homelessness. And with many military women responsible for children the stakes are higher still.

It became clear from Lindsey's story that Mary had really stuck her neck out to get her into the treatment and counselling that she would not have otherwise received from the VA. Lindsey's substance abuse had led to her receiving a less than honourable discharge from service, which meant she was ineligible for benefits from the VA. Mary was outraged by this, and explained to me that it was precisely her experiences in Iraq which had caused her PTSD and, in turn, led to her substance abuse. It was a vicious cycle, which Lindsey was only able to break over time and with Mary's help.

It was incredible to see this young woman struggle bravely with her disease, holding no anger or resentment towards the institution that put her at risk. This was a humbling encounter for me and I came to understand just how important it was not to make a film that was either pro- or anti-military, but to concentrate on Lindsey's journey and new role as an ex-Marine. I was able to witness the remarkable moment when Lindsey learned to once again trust someone.

It was echoed by Mary's words: "If women don't take care of each other, who will?"

This film also explores the growing disconnect between most American citizens and those who serve in their military forces. There is an unspoken, invisible wall between the enlisted and the non-military and I hope that this film can shine a small beam of light onto that division and allow us to start to openly discuss the cost of that divide.

I would love to see the story of Lindsey and Mary spark more dialogue about the effects of PTSD, military sexual trauma, traumatic brain injuries and the effects of war on society and help more brave women like Lindsey receive treatment, begin recovery and discover a new life.

[UPDATE: IN 2012 LINDSEY SUCCESSFULLY WON HER APPEAL. SHE HAS NOW RECEIVED AN HONOURABLE DISCHARGE.]

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