For the last 15 years, whenever anyone asks "How are the kids?", I "laundry list" the four oldest and don't mention DS. I can't stand the sympathy or the judgement. Even our older children don't know everything that has happened, it's just something so personal. We actually even left a small town (moved 4 miles to the country) partially due to the feeling of shame over his antics. Some of it was real--there was a lady who actually called a few times to tell me what my kid was doing. I hardly knew her, she was a friend of a friend. She "thought I should know". We already did, believe me, and I still can't look at that woman. Others probably didn't mention him due to not wanting to hurt me and I felt their love (or maybe they had a Difficult Child in their closet?) 
All of this is why it's so important to go to trusted counselor, Al-anon or a forum of this type. We get you more than you know. There's nothing to be ashamed of, you did your best, now it's time for her to try to do her best. Prayers.
