Shannon Wu and John Sanders attended the same book festival in Washington, but didn’t meet until they connected on a dating app.

A few months after Dr. Orion Mercaitis leased a polo pony from Olivia Stringer in Aiken, S.C., their relationship took off at a gallop.

Jerald Creer, who is deaf, and Kent Williams met on a cruise ship in 2009. It took almost 15 years and a card game for them to fall in love.

Dr. Raymond Parungao and Andrew Chen have had a bicoastal relationship for most or their 15 years together.