没有什么过不去只是再也回不去
[méi yŏu shén me guò bù qù zhĭ shì zài yĕ huí bù qù]
'There's nothing insurmountable; yet we can never go back.' It expresses a bittersweet sentiment that though life moves on after certain changes, what has been lost—often time or a particular phase of relationship—cannot be regained.