I see that the marriage took place in Cooltrain Church of Ireland. Also that Bell’s father was a Butler. Cooltrain COI (also known as Colebrooke) used to be the Chapel of Ease for the Brookeborough family. It’s near their house (Colebrooke). With Lindsay Shaw being a butler, I wonder if he worked for that family?
https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1860/09593/5478706.pdf
I notice that a Robert Shaw was a witness. Bell’s brother perhaps?
A death for a Lindsay Shaw in Enniskillen aged 23:
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_returns/deaths_1897/05848/4656877.pdf
His marriage. Father Robert:
https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1892/10638/5876215.pdf
Robert Shaw’s marriage in 1871 in Aghavea Church of Ireland. Father Lindsay, servant. So it looks like same family:
https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1871/11334/8160048.pdf
Bell was living in Ramult when she married. (That’s about half a mile outside Fivemiletown). No Shaw family there in Griffiths Valuation so she may have been working as a servant for a local farmer.
I looked for Lindsay Shaw after the 1860s but could not find him, alive or dead. By 1901 he was definitely not Lord Brookborough’s butler:
http://www.census.nationalarchives.ie/pages/1901/Fermanagh/Brookeboro/Colebrooker_Demesne/1355799/
This Brooke family had a son Basil b 1888, later known as Lord Brookborough, who became Prime Minister of Northern Ireland for 30 years, so quite a famous family.
One possibility is that Lindsay Shaw died before 1864 when death registration started in Ireland. Though he’s named in the 1860 marriage certificate that doesn’t mean he was alive at the time. Colebrooke COI may have burial records which might show him, if he died pre 1864. You could also search those same church records for Bell’s baptism. Tradition was to marry in the bride’s church. Of course with her father being a butler, he may well have worked all over the country, and she may not have been born locally.