There's a wild conspiracy theory floating around that Matthew Perry's recent "Mattman" posts before his death were a cry for help ... but the woman he dined with the day before he passed says that theory couldn't be further from the truth. Athenna Crosby, the mystery brunette spotted grabbing a meal with Matthew before he died, tells TMZ ... the "Friends" star was really into Batman -- even calling himself "Mattman" and his ride the Batmobile.