As already noted, your flight was cancelled due to a previous operational cancellation.
Most likely the DFW weather mess from the previous day left RIC starting the next day short one (or more) plane. That won't get balanced out until a RIC departure gets cancelled. The inbound plane that you thought should cover your outbound may have been needed more to cover whatever RIC departure was physically shorted. The thing to remember during IRROPS is that not only are the aircraft all out of place but so are the crews. And crews have duty time limits to complicate matters even more. Getting all the pieces of the puzzle back in place after a major IRROPS event is a huge undertaking with "spill over" issues happening the next day being very common. Few aircraft/crews are operating on their normal/scheduled routings/turns/etc.