When an unauthorized edition of The Lord of the Rings was published by Ace Books to get a jump on the official Ballantine Books edition, Tolkien began pointing out in replies to his American fan letters that he wasn't receiving one cent in royalties. When they heard he had been ripped off, many of his American fans tossed their unauthorized Ace paperbacks and bought the Ballantine paperbacks; they also began lodging protests to such an extent that Ace Books agreed to withdraw their edition from the market and pay Tolkien his share.
Tolkien is stated to have considered his wife Edith to have been "his Lúthien". In fact, the name "Lúthien" appears after her name on her gravestone; "Beren" appears after Tolkien's name on his gravestone.
Their entire relationship is one of the sweetest you'll ever read. They were childhood friends, until, aged 16, the priest who was Tolkien's foster father told him to stop seeing Edith until he was 21. He followed through with that, until his 21st birthday, where he wrote a letter to Edith telling her he loved her and asking her to marry him. Despite the fact she was engaged to another man, she immediately broke off the engagement and married Tolkien. Turns out she had also been in love with him, but thought he had forgotten about her.
Of course, there were times where their relationship was tested. Edith was not an intellectual, and is said to be jealous of her husband's friendship with C. S. Lewis. Their different faiths was, for a while, another issue. See that part about the priest above? Edith was Anglican, while Tolkien was Catholic. Though Edith converted, she was never truly comfortable with Catholicism until 1940, where husband and wife heard each other out.