The couple tied the knot in Santa Ynez, California, in 1999, with Marisol wearing a gorgeous satin Vera Wang gown and Rob rocking a Gucci tux.
In the lead-up to their 17th anniversary, Thomas told ET that the pair tend to be low-key when it comes to such milestones.
"We pat ourselves on the back every anniversary, but at the same time, when we got married the idea was that we were going to be married as long as we're alive, so we don't want to make too big a deal out of it,” he explained at the time. “We were always headed this way, so it's just about continuing that promise."
However, that pat on the back is well-earned given the trials the pair has faced, with Marisol beginning a debilitating battle with Lyme disease four years into their marriage.
Having finally been diagnosed with the illness following brain surgery in 2015, she has now become an advocate for tickborne diseases and will be honored for her efforts at Global Lyme Alliance’s 3rd Annual New York Gala on Oct. 11.