When I called Bettye in January 2009 to tell her I was getting married, she cheered. Then, she asked, “What should I wear to the wedding?” But the truth was, I wasn’t sure Jonathan and I were even having a wedding. You see, I was in my early 50s and I thought I was a little too old to march down the aisle.

But Bettye persisted, reminding me that my friends wanted to be part of this important life event; after all, I am a cancer survivor who was in treatment for non-Hodgkin lymphoma back in my 30s, when my peers were busy getting married and starting families.

[See: 7 Innovations in Cancer Therapy.]

Bettye won me over, and Jonathan and I had a wedding, which Bettye and her husband, Tyrone, drove from Indiana to New Jersey to attend. Their participation and support, as well as that of other family members and friends, made the celebration one of the most joyful moments of my life.

In sickness and in health: A vow that is equally important in friendship and marriage. And, for cancer survivors and people living with the disease, this promise often begins with bonding over a shared experience of illness.

Bettye and I are a case in point: She is a nurse from South Bend, Indiana, and I’m a former contemporary art center director who has spent most of her life in and around New York City. It’s almost certain that we wouldn’t have met if not for our shared bond of cancer survivorship and the commitment to cancer advocacy our diagnoses inspired and sustained.

For nearly 20 years, Bettye and I have worked together on advocacy projects, often driven by our mutual devotion to achieving health equity. And, like many who share a common purpose and passion, we have developed a bond of friendship that has enhanced all aspects of our lives.

Throughout the years, Bettye and I met at cancer advocacy and scientific meetings — often those we planned together or at which one of us had invited the other to speak. Sometimes, when our travels put us in the same city, we had time for a purely social visit — say, a shared meal, walk and shopping. (Bettye and I are a little too good at encouraging each other’s shopping habits, especially for jewelry.)

Bettye and I can go more than a year without seeing each other, but like all true, lifelong friendships, we pick up where we left off after five minutes. Deep sympathy and understanding are the threads of our friendship. When I called Bettye back in 2009 to tell her I was getting married, she wasn’t a bit surprised. She had known from my first date with Jonathan that he and I would be life partners.

About 10 years after Bettye and I met, both of us had a difficult year. I had accumulated a lot of airline frequent flyer miles and so we decided to go to Paris. She had never been and had always wanted to see the Eiffel Tower, the Mona Lisa and experience the streets of Paris. She spent days accompanying me to cafes where I drank too many cups of espresso and savored crusty French sandwiches. I followed Bettye to quilt shops and fabric stores. We shopped for shoes and bags and jewelry and went to many of the museums and churches of Paris. Near the end of our trip, we decided to go to the Eiffel Tower. But while we were standing in line, we looked at each other and almost simultaneously realized that we were both afraid to get into that shaky elevator. After years of knowing each other so well, we were not at all reluctant to share our fears.

In March 2014, I called Bettye again. This time, rather than joyful news, I told her I had been diagnosed with breast cancer. We were back to sickness again. Bettye was consistently in touch, checking in with Jonathan and me. About two weeks after my mastectomy, Tyrone again drove Bettye from Indiana to our house in New Jersey to visit me, support me and see with her own eyes that I was OK.

[See: 10 Things You Didn’t Know About Breast Cancer.]

This spring, it was Bettye’s turn to call me to “save the date.” In a ceremony in Indiana in late June, she and Tyrone celebrated their 50 ^th wedding anniversary by renewing their vows. Sitting in that church, I watched as generations of her family and Tyrone’s family, their children, grandchildren and great-grandchildren walked down the aisle before them. Bettye, in a long white gown and a veil that she made herself, and Tyrone, in a handsome tuxedo, renewed their vows surrounded by family and friends. Just as she had wanted to witness my marriage, I was so moved to be at their anniversary.

Many cancer survivors I know became health advocates to help alleviate the loneliness and pain of those who came after them. But, we were also looking for a community of understanding. I found this sustaining community, but I also found precious, lifelong friendship.

[See: 10 Lessons from Empowered Patients.]

At the church in Indiana, I watched the photographer take family photos for nearly an hour. Then, we danced for hours. The deep bonds of shared survivorship and cherished friendship mean witnessing and participating in each other’s lives — in sickness and in health. And in joy.

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Finding Friendship Through Cancer Survivorship originally appeared on usnews.com