放心我会比你更幸福
[fàng xīn wŏ huì bĭ nĭ gèng xìng fú]
'放心我会比你更幸福' (Fàngxīn wǒ huì bǐ nǐ gèng xìnfú) means 'Rest Assured, I Will Be Happier Than You,' indicating that after some form of separation or heartbreak, this person feels they will move on and find greater happiness independently.