This is the one I was thinking of - Fair Haven
Janeway falls in love with a holodeck character from a 19th C Irish village the crew all hang out in to relax (once then never mention again).
The crew relaxes in Paris's latest holodeck creation: an idealized 19th century Irish village, where Captain Janeway falls in love with a holographic character. Tom Paris has created a very detailed program in 19th century Ireland, a town called Fair Haven. He wants it to be a place where the...
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I don't recall any Brigadoon reference in Voyager.
There was a DS9 episode, where Dax falls in love with an alien on a planet that falls in and out of our physical universe every 100 years like a magical village. but that didn't involve a holodeck at all.