The Kendra on Top star took to Instagram on Monday to share the heartbreaking news, along with a slideshow of photos of her beloved Jack Russell terrier.
"Martini has been by my side for 16 years. We will miss her," the 32-year-old reality star and Playboy model wrote in the caption. "This is one dog that has seen n been through it all. Lol from San Diego to the playboy mansion to the east coast to Calabasas. I can say she lived her best life."
Earlier in the day, Wilkinson also shared a forlorn, black-and-white selfie to her Instagram story, on which she wrote "I Hate 2018."
The reality star is understandably wary about the year, which has shaped up to be particularly difficult for her.
According to court docs obtained by ET on April 6, the model -- who tied the knot with Baskett in June 2009 in a ceremony at the Playboy Mansion -- cited "irreconcilable differences" as the reason for terminating their marriage.
In the documents, Wilkinson listed the date of their separation as Jan. 1, 2018. Per the divorce filing, she is seeking to share joint custody of their children.
For more on the couple's split, check out the video below.