Hi Cryfran,
May be barking up the wrong tree here, not very good on Welsh places. There is a Mary Wynne marrying in Llanrwst Caernarvonshire, Denbighshire district in 1861 with no partner. Found her on Ancestry, Marriage 1st quarter, district 11b page 304.
You could always order cert just with the one name.
Hope it helps,
Good luck, Joan