KAT VON D: JESSE JAMES CHEATED WITH 19 WOMEN

Kat Von D claims Jesse James cheated on her with 19 women during their "toxic relationship" ... this according to a rambling confessional she just posted to her Facebook page.

Kat never mentions specifically if that's why their relationship ended, but she does say she deserves a big fat, "I told you so," from everyone:  "You all were more right than you'll ever know."