Was Sheelagh St. Patrick wife?

An early reference to the celebrations on 18 March was discovered in John Carr’s 1806 book The Stranger in Ireland. Carr said that on the anniversary of St Patrick, the country people assembled in their nearest towns and villages and got very tipsy.
It read: “From a spirit of gallantry, these merry devotees continue drunk the greater part of the next day, viz., the 18th of March, all in honour of Sheelagh, St. Patrick’s wife.”

The Journal.ie