Writing from memory (can't play my old LPs anymore) but I think the middle bit of DeD's version goes:

Why didn't you tell me so
Why didn't you tell me so
Why didn't you tell me so
What the devil ailed ye?

How could I tell you so?
How could I tell you so?
For if I did there isn't a doubt
I never would have gained ye

AND:

Why didn't you tell me so
Why didn't you tell me so
Why didn't you tell me so
Before you did the harm?

What harm did I do?
What harm did I do?
What harm did I do?
??? But only in me arm (or something...)

I also seem to remember the final lines of each verse (one refusing to marry, then one agreeing) as being "For why? You are a stranger" and "For sure you are no stranger" though I may be remembering it a bit wrongly. Makes you wonder what they got up to between the first and second verses...