You might be surprised to learn that Benjamin Franklin even had a wife. Deborah Read and Ben weren't legally married because she couldn't prove her long-gone first husband was dead, but they entered into a common-law marriage and Deborah took in Ben's illegitimate infant to raise as her own. The couple had two more children, but eventually Ben's career took him on many trips outside Philadelphia, often to England, and Deborah waited for him to come home. When she died in 1774, she hadn't seen Ben in years.
We tend to idealize our founding fathers. So what should we make of Benjamin Franklin? One popular image is that he was a free and easy libertine—our founding playboy. But he was married for 44 years. Biographers and historians tend to shy away from his married life, perhaps because it defies idealization. John and Abigail Adams had a storybook union that spanned half a century. Benjamin and Deborah Franklin spent all but two of their final 17 years apart. Why?
The conventional wisdom is that their marriage was doomed from the beginning, by differences in intellect and ambition, and by its emphasis on practicality over love; Franklin was a genius and needed freedom from conventional constraints; Deborah’s fear of ocean travel kept her from joining her husband in England and made it inevitable that they would drift apart. Those things are true—up to a point. But staying away for a decade, dissembling year after year about his return, and then refusing to come home even when he knew his wife was declining and might soon die, suggests something beyond bored indifference.
One possibility is that Ben and Deborah parted ways because of the specific circumstances surrounding the death from smallpox of their four-year-old son Francis. Read that story and and more about Ben Franklin's marriage at Smithsonian.