There's been tension throughout Real Housewives of Beverly Hills Season 4 thus far between Lisa Vanderpump and Kyle Richards. But now, things are getting especially vicious.

Following last night's episode — in which Lisa hears that Kyle was speculating that her faint was faked, along with Lisa seeming to suggest that Mauricio might in fact be cheating on Kyle — Lisa took to Twitter to retweet a particularly nasty message from one of her Twitter followers.

"I don't normally retweet... however everybody else is so here we go," Lisa tweets on November 18 before retweeting this: "Talking st about @LisaVanderpump when she's not there is really sucky @BrandiGlanville, especially to fat Kyle. #BadFriend #RHOBH."

So why did Lisa post such a harsh message? "Hard to see all the crappy comments when I was feeling particularly compromised," Lisa tweets. "Not a victim, but the lack of support was disgusting."

As you can imagine, Kyle did not appreciate the fact that the message that Lisa retweeted referred to her as "fat."

"Wow, Lisa. nice retweet," Kyle tweeted. "Thanks for the RT calling me fat. #mean."

When a Twitter follower responded that Kyle was mean to Lisa by implying that she faked the faint, Kyle responds, "[I didn't say] mean things about anyone specifically. Purposely did not."

And when a Twitter follower tells Kyle that Lisa is a great friend to her, Kyle pointedly says, "On camera." Kyle adds, "And what about the 'where there's smoke, there's fire' comment? Deliberate — believe me."

This leads Lisa to tweet at Kyle, "Thanks for your piss-taking... #evenworse."

Wow! We had hoped that Kyle and Lisa would have worked out their issues of late, but they are clearly not in a good place. 

Do you think Lisa went too far by retweeting a message that calls Kyle "fat"? 

Source: Lisa on TwitterKyle on Twitter