Regardless of what happens in the rest of The Witcher games, one modder has decided Geralt and Yennefer will get a happy ending. This mod for The Witcher 2 will give an epilogue to the whole series, that lets Geralt of Rivia settle down, once and for all.
Called The Witcher: Farewell of the White Wolf, the mod acts as a piece of story DLC, with three days of questing for Geralt and Yennefer’s wedding. Friends and guests from through-out the RPG game’s storied history will pop in to see the two find a quiet life together. “It tells about a wedding of Geralt of Rivia and Yennefer of Vengerberg, two people destined to each other, who finally found a little peace,” the description on Nexus reads. “During three days (and even more than that) of adventures, you’re going to see the returns of Geralt’s closest friends, unexpected guests, interesting stories, and more than just one romance.”
Scripting and development has been going on since 2015, three main developers, Konrad Chlasta, Kamil Leniart, and Patryk Adamkiewicz, working with several other contributors for the translations, music, and design. Six languages are available, and the Nexus page lists some known bugs in case something goes wrong.
Original source: https://www.pcgamesn.com/the-witcher-3/mod-geralt-yennefer