The reason why Lucy got any "Points" was because of Don Corleone. Remember The Don knew about Sonny messing around with Lucy which he didn't approve of at all. When Lucy tried to kill herself after Sonny's Death, Tom Hagen on orders of The Don decided to take care of her as well as Sandra and his Grandchildren.

I believe that he did it more out of guilt because he felt that Sonny had no right to be messing aroung with Lucy in the first place and to try to kill one's self was to him a major sin.

I also believe that The Don felt that not only was Sonny a bad Don, but a bad Husband as well.