A fair amount of thumbling tales mention marriage. However, I had thought that Tom Thumb was doomed to die young and childless. Most renditions of his story end this way, which is honestly a bit of a downer. However, it turns out a few authors have seen fit to set Tom up with a lady friend.
Princess Huncamunca in the play Tom Thumb by Henry Fielding (1730). The play would later be edited and expanded as The Tragedy of Tragedies, but the central idea was the satire and a huge, tangled love dodecahedron. Like most of the cast, Tom has multiple love interests; in his case, these are King Arthur’s wife Dollalolla, Arthur’s daughter Huncamunca, and the giantess queen Glumdalca. In 1733, it was re-adapted as The Opera of Operas; or Tom Thumb the Great, by Eliza Haywood and William Hatchett. This focused more on parodying opera tropes, so the the ridiculously tragic deaths are reversed and Tom marries Huncamunca.
Tom Thumb and Hunca Munca were the names of Beatrix Potter’s pet mice and the stars of The Tale of Two Bad Mice.
Grumbo’s daughter, in “Tom Thumb's folio, or, A new penny play-thing for little giants,” printed in 1791. This version dispensed plenty of details. Tom’s father was Theophilus Thumb and the family was from Northumberland (ha.ha.ha.). Tom was born in 1618 on the day of a solar eclipse (July 21?). In this story Tom defeats Grumbo, king of the giants, and becomes a major political force in the kingdom. (This is very different from the typical story where he functions solely as a knight and a sort of clown whose duties seem to boil down to performing for the king - he doesn't actually do much other than make a good appearance.) He marries Grumbo’s daughter, an unnamed giantess. They have twin boys named Gog and Magog, “nine hundred times” as big as Tom.
Princess Poppet in “Harlequin and Tom Thumb, or Gog and Magog and Mother Goose’s Golden Goslings,” a pantomime performed in 1853. Here, Tom rescues King Arthur’s daughter Princess Poppet from the giant Grumbo. Arthur is reluctant to bless the marriage, but Mother Goose shows up and there’s a harlequinade and Tom and Poppet get married. Apparently the pantomime was fun, if somewhat incomprehensible to some critics.
An unnamed bride in Extraordinary Nursery Rhymes and Tales: New Yet Old (1876) features retellings of fairy tales and nursery rhymes in verse. Here, with help from King Arthur and the fairies, Tom Thumb begins looking for a proper wife. At first he can’t find a girl of proper size, and then he meets twenty little fairylike beauties and can’t choose between them. However, he eventually ends up with one and is perfectly happy (the other girls serve as bridesmaids). His new wife has six babies per year, alternating between daughters and sons, and they need help from Arthur and Guinevere to feed them all.
Queen Smilinda in The Lilliputian Magazine; or, Children's Repository (1770s) contains a story called "The Lilliputian History," detailing the life of a King Tom Thumb of Lilliputia. The story is original, but begins with King Thumb visiting the court of King Arthur in a clear nod to the British tale. Smilinda is the princess of a country called Yarthonia. They have a son, born in 1514, whose name is not given.
The most common names in Tom Thumb weddings were Lillie Putian (with many variations) and Jennie June.
This website is based on my research into folklore.