Jesse James is using his Twitter account to prove he's a changed man -- "I wish people would give me a second chance," he wrote, quoting disgraced baseball player Pete Rose. "I won't need a third chance." -- but there's one girl who's not buying it.
His ex-mistress, Michelle "Bombshell" McGee, who has a harsh message for the biker's new fiancee Kat Von D, 28.
"Kat what in the world are you thinking?" the tattooed mom of two, told RadarOnline. "I was with Jesse during his marriage -- the guy's not faithful, he doesn't have a faithful bone in his body!"
Continued McGee, who was just one of the many women James cheated on ex wife Sandra Bullock with, "If he did it to me, if he did it to Sandra, he's gonna do it to you, too -- once a cheater always a cheater. He cheated on his wife, numerous times."
And though James, 41, attempted to make amends following his split from the Oscar winner last spring, McGee isn't buying it.
“I guess he went to sex rehab, maybe he’s reformed, he’s all better,” she said, laughing, before adding, "From my experiences, he’s a pig."
McGee, who said she's never met the L.A. Ink star and hasn't spoken to James since before the cheating scandal broke, did have one offer for the twosome, though.
"Jesse and Kat, I want to say I'm going to be throwing your bachelor and bachelorette parties -- if you ever make it to the altar -- as well as your divorce party."