Friends To Frenemies: Where It All Went Wrong For ‘RHOC’ Estranged BFFs Shannon Beador & Vicki Gunvalson

The Real Housewives of Orange County is done filming for the season, but the drama is far from over!

Before the taping of the reunion special last week, Shannon Beador added even more fuel to the fire between her and co-star Vicki Gunvalson when she revealed that the finale would likely be "Shannon versus Vicki." Now, a source close to production for RHOC tells RadarOnline.com exclusively that their friendship was broken months ago!

According to the source, their relationship changed forever when the two ladies had lunch together in the OC to talk about Brook Ayers' cancer diagnosis.

During the meal, which appeared on an episode of the show, Beador tactfully told Gunvalson that the situation could be resolved if she would provide documents proving that Ayers does, in fact, have cancer.

A source close to Gunvalson told Radar, "During that lunch, Shannon should have just been a listening ear and a friend. That is all that Vicki wanted her to be at that moment. Instead, she pushed and pushed when Vicki was really just wanting to have someone to talk to."

"The only thing that Vicki is really guilty of in all of this is loving Brooks," the pal told Radar.

However, according to a separate source close to the cast, "Shannon just feels that this whole thing has been blown way out of proportion and it feels like Vicki is trying to deflect all of the blame on her."

"Yes, the feud did start at that lunch," said the source. "Shannon told her to get medical records because she was trying to be honest with her. That's what friends do. Shannon was only saying that out of concern and she was just trying to find a solution."

"But instead of taking her advice, Vicki completely turned on her. Shannon has not changed her stance on this and Vicki knows the truth," the source added.

Are you Team Shannon or Team Vicki? Let us know in the comments!