what to do about a friendship?

[DONNA1458]

I was out with my cousin who has been close to me all my life we are a year apart, she has a very up and down relationship with a guy who is very possesive and if you tell her anything in confidence she will always tell him, she has met my fella of 3yrs 3 times and on friday night told me that her bf who has only met mine twice thinks he doesnt love me and that her brother is a sleaze and she TELLS me that im not happy that i dont get as drunk and silly as five years ago,i told her thats because im diabetic now i cant drink as much and i have grown up so im not a silly anymore (26 now) i am really happy with plans for the future but she by her own admission thinks she can do better and is taking the pill secretly because she has told him she is off it, i could have metioned these things to her and have a look in the mirror but i dont want to argue. what should i do leave things to cool down or put the record straight she and her bf should not be making judgement on me.