MORE SHOCKING! They split because Brendon sent photos of his PENIS to another woman!
In one of the most ridiculous, cry-babyish, pathetic videos to ever hit the web -- Brendon recorded an apology to his former reality TV show girlfriend for sending shots of his wang to some chick he met online ... who then released them into cyberspace.
Brendon claims he was duped by the naked photo recipient -- who allegedly threatened to blackmail the swim coach if he didn't send her video of himself.
Brendon -- who cries more than a 13-year-old girl at a Justin Bieber concert -- claims he wants to spend the "rest of his life" making things right with Rachel.
If she'll ever talk to him again.