I have a friend whose panic attacks are so severe that they once triggered a seizure. Sonja was, understandably, hesitant to travel — afraid that the little stresses along the way would turn into a big medical emergency. That is, until a small, friendly dog named Montecristo entered her life, helped her manage that anxiety, and, in her own words, “gave me back the joys of travel and being off medication.”

My own story is similar. When I met my dog, Luna, I was in the throes of a deep and dangerous depression. My doctor put me on antidepressants because I wanted to die. I don’t think I would have harmed myself, but I had started secretly hoping that the universe would do the job for me. That a bus would hit me or I’d accidentally overdose or simply that I’d be allowed to exit the earth quietly and gracefully, to just erase myself.

Then there was Luna. Tiny, curious, energetic Luna, whose joy over playing with a hand towel was immense and contagious. Luna made me laugh when no one could make me laugh. The simple act of petting her eased the pressure in my chest, the impending panic attack.

Luna didn’t erase my depression. I wasn’t magically better from that day on. But she gave me moments of joy, pinpricks of light at the end of the tunnel where I hadn’t seen any before.

The most important thing Luna did for me, though, is make me stop thinking about dying. Because even on the very darkest, hardest days, Luna needed me. I was responsible not only for my own life, but for the life of another — another that I loved desperately and who needed me just as much as I needed her.

I did a thousand other things to pull myself out of depression, to make life better, to learn to love myself, to learn to manage my anxiety. But Luna is the one thing that could always get me out of bed and to work, even when I wanted nothing more than to sleep forever.

Both Luna and my friend’s dog are emotional support animals (ESAs), a title that, in the United States, gives us a few benefits: First, that no U.S. landlord can deny us housing with our dogs and, second, that U.S.-based airlines must allow us to fly with our dogs in-cabin with no fee.

Because of these benefits, ESAs can draw a lot of criticism. I’ve heard people say that if we’re such big babies and can’t fly without our pets, maybe we shouldn’t fly at all. Other people say that we should pop a Xanax (why is medication always the answer?). Still others roll their eyes and call us fakers, selfish, system-players. They don’t believe that there is such a thing as an invisible disability. I’ve even been called a “twat.”

Which is why I want to tell my story, why I want you to know how Luna saved me, why I want you to know that I might not be here today if Luna had not entered my life. There’s a big misconception in America, that ESAs are for people who get nervous in flight. That people need to man up and just face their fear of flying.

But that’s not what ESAs are.

Just like full-fledged service animals, ESAs are about the freedom and health of a disabled person. They are about allowing someone with an invisible disability the same freedom — to visit their families, move across the country, or simply find a place to live — that is afforded to people who have never had to experience the depths of depression or anxiety attacks that led to seizures.

Because of her dog, my friend has traveled the world, sailed in the Mediterranean, and been able to stop taking medication.

Because of my dog, I am not only alive, but am living my life to the fullest. I travel the world. I own my own business. I’ve found ways to make my anxiety and depression smaller, more manageable, and hopefully someday gone altogether.

Just like therapy, doctors, medications, exercise, massage, etc., ESAs are a tool to manage an invisible disability. These dogs (and cats) have changed a lot of lives. In ways much bigger than you could imagine.

So, as I have many times before, I send a whispered thank you into the sky for Luna and all the dogs (and cats) like her who have made life possible, bearable, and even joyful for those of us who struggle. And I hope that by telling my story, I can start to create just a little more clarity, compassion, and understanding about what ESAs really are and how very much we need them in the world.

Do you have an emotional support animal? How has he changed your life? Let us know in the comments!

Learn more about dogs with Dogster:

• The 10 Naughtiest Dog Breeds
• The World’s Most Popular Dog Names for 2013
• 5 Myths About Dog Behavior That Often Lead to Tragedy

Read more by Gigi on ESAs and traveling with your dog:

• Q&A: How I Travel Internationally with a Large Dog
• Britain Denied Me Entry for Traveling with My Dog, an Emotional Support Animal
• The 5 Stages of Dog Jet Lag
• The Beginner’s Guide to Flying Internationally with Your Dog
• Three Unexpected Benefits of Traveling with a Dog

About the author: Gigi Griffis is a world-traveling entrepreneur and writer with a special love for inspiring stories, new places, and living in the moment. In May 2012, she sold her stuff and took to the road with a growing business and a pint-sized pooch. You can follow her adventures at gigigriffis.com or friend her on Facebook.