How do i tell her she has mouth odour

I have been with my GF for 3 months now..she is really cute and loaded but i have 1 major problem with her, she has bad mouth odour(halitosis)..sometimes when we cuddle and she talks to me,i have to be holding my breath at intervals and seriosly,i can't do it anymore. i feel i would hurt her if i tell her that her mouth stinks. 

pls is there any other way i can tell her without necessarily telling her straight.trust me i have tried the method of giving her gifts of mouthwash and mint sweets.