If I could sidetrack this thread for a moment -- Jim, is there more than one song called 'grá geal mo croí'?

Folk Songs of Australia contains a song called 'Gargal Machree', which was collected from an Irish emigrant and includes a verse very similar to the one you quote. The editors note that the title sounds like a corruption of 'grá geal mo croí' but they say that the Irish songs of that title are completely different.