Ashley Graham is ditching hubby Justin Hervin on Valentine’s Day to walk Sports Illustrated Swimsuit’s red carpet — but don’t worry, they’re keeping the spark alive.

“We like to walk around the house naked together. It keeps things fresh,” she tells The Post at the launch of Marina Rinaldi Denim, Graham’s new plus-size jean collaboration.

Graham, a longtime advocate for body diversity in fashion, wants women to feel just as confident clothed in her pieces for the Italian brand.

“Our sizes run up to 22,” she says. “I wanted to create something that’s inclusive for all women.”