Thank you Felipa , I investigated and found that "The Banks of the Roses" is often a murder ballad which doesn't mention getting married in May but below are some links where your married in May verse is sung .

And when I get married t'will be in the month of May
When the leaves they are green and the meadows they are gay
And me and me true love we'll sit and sport and play
By the lovely sweet banks of the roses
BANKS OF THE ROSES (THE)

The Banks of the Roses - The Dubliners     https://www.youtube.com/watch?v=5TaICG7bnHk
Luke Kelly Banks Of The Roses  https://www.youtube.com/watch?v=vvl7DHPiU04
Banks Of The Roses · Nathan Carter   https://www.youtube.com/watch?v=rXoLf3ZXMjY
On the Banks of the Roses - The Corrie Folk Trio    https://www.youtube.com/watch?v=nOiM1UmjPjM
The Barra MacNeils - Banks of the Roses    https://www.youtube.com/watch?v=L3MzZlEvCJY