Martin Graebe has written a very interesting book about SBG and his folk song collecting (which also functions as a general biography), called As I Walked Out. Worth tracking down if you want to learn more about him.
I loved the story about how he met his wife, when he was a curate in Yorkshire. She was a mill-girl, quite a bit younger than him, and far below him in social status (this was the 1860s, so these things mattered). He was determined to marry her, and arranged for her to spend a year or so living with a middle-class family to learn how to function in those circles, whilst he paid her family the equivalent of her wages. They were happily married for about 50 years, and had 15 children, and are buried side by side in the churchyard, and his epitaph for her calls her 'the better half of him'.