What was the name of Tolkien's wife and longtime literary collaborator?

Tolkien's wife and longtime literary collaborator was Edith Tolkien.

Edith Mary Tolkien, born Edith Bratt, married J.R.R. Tolkien in 1916. Their relationship began when Tolkien was a teenager, although his guardian initially restricted contact between them. Their marriage lasted until Edith's death in 1971, and they had four children: John, Michael, Christopher and Priscilla.

Edith influenced Tolkien's imagination and is widely associated with the character Lúthien. Tolkien regarded the story of Beren and Lúthien as deeply personal, and he had “Lúthien” carved on Edith's gravestone. “Beren” was later placed on Tolkien's own gravestone in Oxford.

Christopher Tolkien became the principal editor of many posthumously published works, but he was Tolkien's son, not his wife. Edith also supported the family through wartime separation and the demanding years of Tolkien's academic career.