was this lady ever married?
Yes, she married Thomas Leon Owens.
Anna Leonowens
, Anna and Thomas Leon Owens married on Christmas Day 1849 in the Anglican church of Poona. 
where did the king and i come from It is based on Margaret Landon's novel, "Anna and the King of Siam" is it  based on any events in history? Yes, it is derived from the memoirs of Anna Leonowens, governess to the children of King Mongkut of Siam in the early 1860s.
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Anna Leonowens [SEP] Marriage, Western Australia and widowhood
Nevertheless, Anna and Thomas Leon Owens married on Christmas Day 1849 in the Anglican church of Poona. In the marriage certificate, Thomas merged his second and last names to 'LeonOwens'. Patrick Donohoe signed the document as well, contradicting Leonowens' account that her stepfather had violently opposed the marriage. She gave birth to her first daughter, Selina, in December 1850. The girl died at just seventeen months. In 1852 the young couple, accompanied by Anna's uncle, W. V. Glasscott, sailed to Australia via Singapore, where they boarded the barque "Alibi". The journey from Singapore was long and while on board Anna gave birth to a son, also named Thomas.