One more thing - we know Lanza was not above communicating via private message on the forums. There were people who shared these messages later on (and in one of them Lanza confirmed that he is experiencing psychotic episodes).
What I mean to say: If he did it on the forum, he may have done it in other places. IIRC, youtube back in 2010 still had a feature that allowed you to send private messages to other users via that platform.
For the record: Lanza never sent me any private messages. I can't remember if it was because he never tried, or because I turned down a friend invite from him.
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Life is like a tram - you need to know when to get off.
"Bullet Time" - a school shooting film from Poland