it's (或 that's) someone's funeral

(informal)used to warn someone that an unwise act or decision is their responsibility

(非正式)［用于提醒某人須對本人的不智行動或決定自負責任］后果由…自負

‘I won't discuss it.’ ‘Don't then—&B{it's your funeral}.’.

“我不想談這事。”“那就別談——后果你自己負責。”。