This means being fond of one's husband, the partner to uxorious, of a man who is fond of his wife to the point of doting excess. Maritorious is much less well known, to the extent that I have had no success in finding a modern example of its use outside the books on words that cite it.
A Google search turned up what looked at first sight like several examples, such as the surprising statement that “Medals and prizes are given to maritorious students”. It took a moment to realise that should have been meritorious. As it happens, that’s oddly relevant, since the only example of the word on record is in Bussy D’Ambois, a tragedy by George Chapman of 1607, in which he coins the word to make a bad pun: “Dames maritorious ne’re were meritorious”.
John Keats’ poem, On First Looking into Chapman’s Homer, refers to the same man, who made a famous translation of the Greek work. Dryden thought little of Chapman’s play, finding in it “a dwarfish thought dressed up in gigantic words, repetition in abundance, looseness of expression, and gross hyperboles; the sense of one line expanded prodigiously into ten; and, to sum up all, incorrect English, and a hideous mingle of false poetry and true nonsense”. However, the Oxford English Dictionary has 116 citations from it, and it has provided modern writers on words, such as myself, some small subject matter, so it hasn’t proved entirely valueless.
The word is from Latin maritus, husband.