Unfortunately, your argument's undermined by the fact that sitting here on PF.com and working on getting a date aren't mutually exclusive.
Furthermore, perhaps the single people just got dumped by a significant other and have every right to feel low about themselves. January's the largest month for breakups, and if it spills over into early February, we've got a lot of people mourning losses of love, who, on this day in particular, only want to be with the one they gave their heart to, nobody else.
One cannot generalize in such a way as to make all single people who mention they're single on an online forum with a parenthesis and a colon appear as a group of lazy whiners who are too slothful to try to get a date. It's illogical and insensitive.
EDIT: Also, Dave couldn't get a date if he paid for one.