06/25/2013 04:54 pm ET Updated Dec 06, 2017

Lesbian Mom in Colorado Could Be Among First to Receive Green Card When DOMA Is Struck Down by Supreme Court (VIDEO)

Catriona Dowling and Cathy Davis first met in 2006 on a mountain climbing expedition in the Himalayas. Though Cathy lived in Dublin, Ireland, and Catriona lived in Boulder, Colo., they had an instant connection. After returning to their respective homes, they began a long-distance relationship, falling in love and visiting each other as often as they could. Their exhilarating reunions ended with tearful goodbyes, then long separations. As with many gay binational couples, it was only when they found themselves searching for a way to be together that they realized the severity of their situation. U.S. immigration law does not provide any way for a gay or lesbian American to sponsor his or her foreign-born partner to live and work in the U.S. Even if a same-sex couple is married, the American cannot petition for a green card for his or her spouse.

Finally, after two years, Cathy secured a work visa when a hospital in San Antonio, Texas, sponsored her to work as a nurse. Along with their young son, whom they'd adopted from Guatemala, they relocated. For three years, they enjoyed some semblance of stability. They grew their family, adopting two girls from Haiti. Cathy was promoted, and her employer petitioned for another work visa when her first was set to expire.

In January 2012, Immigration Service denied this petition, forcing Cathy and Catriona to make a heartbreaking choice: Either Cathy would remain in the United States or she would leave and their family would be torn apart. They chose to stay together and fight.

Their first step was to get married. Obviously, they could not do this in their home state of Texas. They had decided to relocate back to Boulder, but Colorado also has a constitutional ban in place against marriages between people of the same sex. In May 2012, Cathy and Catriona married in Council Bluffs, Iowa. Catriona recalls, "It was a very special day that allowed us as a couple to declare publicly what we had already declared in private six years prior: our love and commitment to each other."

With their family settled back into their beloved mountain town, Boulder, Catriona filed a green card petition for Cathy, just as any other American would do for their foreign-born spouse. There was a catch, however; despite the fact that they were legally married, a federal law called the Defense of Marriage Act (DOMA) prevented recognition of their marriage for immigration purposes. Despite the possibility that their case could be denied, they persisted, determined to protect their future as a family. With hundreds of other couples, they joined The DOMA Project to fight for a secure future for their family.

In January 2013, Cathy and Catriona attended their green card interview at the Denver immigration office. Piles of paperwork were reviewed, and they were questioned about their relationship, their children, and their life together as a married couple. They returned home to await a decision, worrying every day in the six months since that they would be denied. Their case is still pending.

Throughout Cathy and Catriona's relationship and their enduring fight just to be able to be together with their family, the world around them sometimes seems to be changing at lightning speed. When they met in 2006, only one state in the U.S. permitted gay couples to marry. Today that number is 12 (plus the District of Columbia). Even Colorado now permits same-sex couples to enter civil unions under state law. But most importantly for them and the approximately 40,000 other gay binational couples living in the United States, the Supreme Court heard oral arguments in a case that would decide whether their marriages must be recognized by the federal government for all purposes, including immigration. A ruling in their favor would usher in a new chapter in our nation's history, extending the promise of equal protection to lesbian and gay Americans.

For Cathy and Catriona and their three children, everything is at stake. If the Supreme Court strikes down DOMA tomorrow, Cathy could immediately receive approval of her pending green card application. If the law is upheld, she will have no lawful status in the United States and she will be forced to leave the country and move thousands of miles away from her spouse and children.

The cruelty that DOMA has visited upon couples like Catriona and Cathy is immeasurable. That children are caught in the crossfire is unconscionable, especially because the bedrock foundation of United States immigration law is meant to be family unification. With Congress unwilling to include LGBT families in its current immigration reform efforts, the Supreme Court is their only hope. A ruling in the DOMA case is expected tomorrow at 10 a.m. Eastern time.