I think that sense of delusion and what draws people to it might have been part of the theme...although Morehouse obviously didn't think the fictitious Paperwhite would be interested in him if she knew the extent of his disability.
I thought the book was very good at showing the reasons people bury themselves in online worlds. Some people, like Gus, have a reason to be unhappy and you could feel sorry for them, but they put themselves so, so much in the wrong with what they do (even if Gus hadn't murdered anyone, he was a bully, a stalker and a harasser and abused the power he had within the circle). Others, like Morehouse, are just so very vulnerable and don't do anything wrong.
And also, having embedded yourself in that world, the power it then has over you. So some anonymous Internet person can talk at you like Jonny Big Bollocks and order you to stay up all night even when you have work the next day And you're so invested in this world that you aren't able to tell them to fuck off and log off, even though in theory that's all you have to do...the power is entirely self-perpetuated but that doesn't mean it's not there.
And of course, sometimes these people, as pathetic as they are, are also very dangerous in reality.