Dunham was in a five-year relationship with Jack Antonoff, which ended in December 2017.
Miley Cyrus, 28, was first romantically linked to Simpson in October 2019.
The two were first linked in August 2020 and have been keeping a low profile on their affiar.
They have since worked on multiple projects together including 2014’s Life After Beth and 2017’s The Little Hours.
Bell, who married Shepard in 2013, further added that she has yet to ask him to take the test.
Currently, she lives in Nashville near her daughter, Cherish, and two grandsons.