Giving up

I have a friend who was placed in foster care as a child. Now as an adult, she is trying to locate her birth family. We have found some siblings, but she still has a sister she has been unable to find. Recently she learned through DNA that her biological father is the man who abused her when she was little. She had always hoped that wasn't the case. Now she wants to stop the search. She said she has found enough and can't take anymore. Have any of you ever reached the point where the information was too much and you just wanted to stick your head in the sand?