Maria comes off as insecure and bitter as always.
There is nothing to prove that Serena was talking about her. The interview was in March, way before Maria and Grigor's PR-relationship went public, so it makes no sense for Serena to say that she goes on about her boyfriend in every interview. I think she was probably talking about Wozniacki, who does desperately go on about her boyfriend every chance she gets and will never be invited to the "cool parties" because she's so lame and desperate.
Maria is still shook from her 13th straight loss to Serena and it's really coming through in her comments lately.