Sometimes people "forget" things because of the pain. I am sure she remembers the things that happened to you, but does not want to relive the pain and talk about it. It might be hard on your mother to see get upset, so she just simply does not bring it up. She isnt being mean or ignorant, just trying not to bring back those negative feelings. If she doesnt bring it up, perhaps she feels that you will forget about it too. Maybe she feels upset that she couldnt keep you out of harms way and feels too gulity to talk about it, parents seem to go through that a lot. You can try talking to her as letting her know that discussing things in the past are helpful (if that is the case).. or maybe you can leave it alone knowing that she does care, she just doesnt want that memory to cause any more pain.