First post; great site you have here guys.
I reckon they'd been seeing one another "casually", and then she's tried to break it off once he started getting a bit serious. We know from the FB posts about V that he is a bit obsessive, and also that SC was recently out of a relationship as well so probably not in a great frame of mind to make the wisest of choices. What started as a bit of a "lets comfort one another in the wake of our break ups" went a bit far too quickly, and SH didn't deal with it like 99.99% of people would have.
MOO.