Surprised someone downmodded me for this one. If you actually read the article, she wasn't literally talking about living in an overcrowded neighborhood and wanting to move to a big, secluded house; she was talking about feeling bombarded with tweets and wanting to get out of the Twittersphere, where she's not really well accepted.
You know, writers sometimes use these things called "metaphors" to make their points more interesting ... :P
Context is everything, in this case the context is Sterling's assertion that connections is for poor people. So the context is rich versus poor. "A big, secluded house" is correctly a metaphor, but a shallow one, namely for living the style of life of rich people. Something that really is a whole lot easier if you have a lot of money.
This makes your original question seem weird, you are basically asking "What prevents her from living like a rich person?". The answer to that one is obviously "Lack of money".
> And what is stopping her from doing that?
Lack of money, perhaps? Even the non-material first part
>> among family and friends
can be difficult if everyone are busy making ends meet.