"50. David Loomis, … m. Dec. 8, 1692, Lydia, … dau. of John & Deborah (Denslow) Marsh and Hepzibah (Ford) Marsh, and widow of Richard Lyman."
The sentence is confusing. Hepzibah Ford married, first, Richard Lyman, and, second, John Marsh. Lydia Marsh was the only child of the second marriage.