"Happy 18th! Anniversary to the love of my life Bobby Zarin. Bobby is the most perfect man I know. He never loses anything, never forgets anything and when I think he is wrong... he is always right!" she captioned a picture with Bobby. "Truly a Love Story."
Zarin followed up by sharing a collage of photos with Bobby from throughout the years. She included a screenshot of her husband from an episode of "The Real Housewives."
"Happy Anniversary to my Bobby Zarin .. a lifetime of memories..." the star wrote.
Zarin and Bobby celebrated their anniversary amid Bobby's ongoing battle with cancer.
Bobby was first diagnosed with thyroid cancer in 2009, and learned in November 2016 that the disease had spread to his brain.
"Bobby is really strong. He's really fighting," a source told Us Weekly in November.
"Jill has been by his side, trying to do little things to make him happy and make his day."
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