Clarissa; or, The History of a Young Lady (Samuel Richardson, 1748)

This is "a landmark 18th-century epistolary novel by Samuel Richardson, published in 1748, about a virtuous young woman, Clarissa Harlowe, who defies her family's wishes to marry a wealthy man and instead flees with the charming but villainous rake, Robert Lovelace, leading to her tragic downfall."

Here we are closing in on 300 years later - it's still considered the longest novel ever written - I read that it has 950,000 words and originally was published in seven volumes.

Which is why I quit about 10% of the way through (already a lot of reading!) I enjoyed the part I read but do not want to commit the time to read the entire novel. The epistolary method was working quite well, but still.