Friends?: No, but at least not enemies?
Proof: ...that is until Teresa gets so angry at Melissa that she goes to sit with Caroline and they have a semi breakthrough. Caroline was even able to touch her leg!
Friends?: No, but definitely not enemies
Proof: Caroline definitely wouldn't have sat down with Teresa to mediate her family drama in Season 4, so this is growth, but it wasn't exactly a warm and fuzzy luncheon.