Hi Duncan,
Oh, what a wonderful tribute to Ann!
It tells those who never knew you as a couple some details a) about Ann herself and b) your life together, to form a picture of a loving, contented marriage, literally "until death do us part".
I didn't know the song
Tangled Up in Blue (whilst I wouldn't go quite so far as to call Bob Dylan a "snarling villain", I must admit I was never a fan of his) so I Googled it to get the tune, as your poem is set to it. I didn't listen for very long... (sorry!) but I'm sure I'll get to hear you sing Mrs MacLovely Ann at some stage.
So, at the moment, it's a poem to me, rather than a song, and as such all the times you write
an' instead of
and - I think it's nine times - and also
nothin', I'd much prefer to see the full words; you no doubt
sing it that way, as singers often do, but on the page I don't see any advantage in the abbreviations because it's not as if you're losing any syllables.
With that in mind, as there are three in quick succession, you could maybe lose one
an' here:
We got a dog, quadruple-crossed,
so full of love an’ grace,
an’ gradually we kind of lost
I haven't any other quibbles (I like that word

). I think it's an altogether-lovely-poem!
Jayne