Casey Johnson's Ex -- STFU, Tila

1/7/2010 4:27 PM PST

Casey Johnson's Ex -- STFU, Tila

Jasmine Lennard -- Casey Johnson's ex-GF who the late heiress allegedly robbed last year -- had her lawyers fire off a cease and desist letter to the host of Tila Tequila's blog over a ruthless, expletive-riddled blog post.

Tila took to her blog this morning to tear the English model to shreds in the wake of Casey's death -- claiming Jasmine ruined their lives when she reported Casey's alleged burglary last year.

Tila's tirade includes a list of insults that would shock Ozzy Osbourne -- calling Jasmine a "prostitute," "b*tch," "c*nt," "drug addict," "con artist," and ... well, the list goes on.

Jasmine's lawyers are threatening suit if the post is not taken down ... STAT.