Sentence:  When they've got nobody but themselves to think of it don't so much matter as I know of; but to keep on breaking the hearts of those as never did you anything but good, and wouldn't if they lived for a hundred years, is cowardly and <WSD>unmanly</WSD> any way you look at it. 
Meaning of the word marked with <WSD> tags:  Cowardly, base.