Gronkowski announced his first retirement from football in March 2019. At the time, Kostek expressed her support in an interview with Extra, per People. She also said she wasn't sure he would stay retired. (He returned in 2020.) "I think he is messing with everybody, then again he stumps me all the time so who knows?" she said. "He could be pulling this out of the woodwork at some time. I would love to see him out there, but I am also respecting him taking this time for himself, healing up his body, and enjoying the time off."
Kostek also discussed Gronkowski's career. "It's been a blast," she said. "I was cheerleading on the sidelines in the first couple years . . . I went from cheering him on the sidelines of the Super Bowl to being a proud girlfriend in the crowd to [watching him end] his career on the Super Bowl field . . . I feel very lucky that I got to be a part his incredible career."