Marty can't see how she's contributed to her son becoming a murderer before his 21st birthday. she failed to see the problem when he beat Todd nearly to death. She failed to see the problem when he paralysed Matthew. She didn't see a problem when he attacked and tried to rape Starr. She failed to see his drug problem. She's raised him to be a violent, out of control, SOB who shows no remorse and would have continued on this destructive path, murdering and attempting to murder anyone who got in his way. At least Starr and Hope won't be in danger form his anger, because he really was showing signs of being an abuser.