Longtime couple Ethan Zohn and Jenna Morasca have broken up after 10 years of dating.

“It is with much consideration and a heavy heart that we are announcing that after 10 years of a loving relationship, the decision was made to move on without each other,” the couple said in an exclusive statement to PEOPLE this morning.

“We will carry with us the memories of a relationship grounded in love, laughter, support and friendship,” the statement continued. “We have experienced some of life’s greatest joys and toughest challenges together and our decision to be apart can never diminish that. We want to thank everyone for their support and we ask that our privacy be respected as we move forward.”

Such sad news! Morasca, 32, and Zohn, 38, first started dating after meeting on Survivor. Jenna won Survivor: Amazon, and Ethan won Survivor: Africa. They also competed together on The Amazing Race, and starred in their own show, Everyday Health.

Most memorably, Zohn chronicled his very moving battle with Hodgkins lymphoma here on PEOPLE.com – from diagnosis to remission to its return in 2011. He underwent a stem-cell transplant in February 2012, and through it all, Morasca was by his side as both were outspoken supporters of cancer survival and detection. Zohn even ran the New York City marathon in 2011 in support of a cure.

Zohn was there to attend Morasca’s May 2012 graduation from Columbia University, where she earned a master’s degree in counseling and clinical psychology.

“To see her battle through all sorts of challenges and still find her passion for academics is such an inspiration,” Zohn said at the time, calling her “Miss Smartypants” and adding: “Plus, now I don’t have to pay for therapy.”

I wonder why they broke up. Did one of them want to get married? Have kids? Maybe they just grew apart? I can’t imagine going through what they had to go through with his cancer, and then split up after.