ないんだよ

don't ... you know

→ 無い
phrase Common #2,532
don't ... you know An informal sentence-ending expression that emphasizes a negative statement or explains a situation. The よ adds emphasis; when followed by ね, it can seek agreement or confirmation.
JA: 今日は宿題がないんだよ。
EN: I don't have homework today, you know.

居場所がないんだよ

I feel like I have nowhere to belong.

— ファイト・クラブ (1999)

食べてる時間ないんだよ

I don't have time to eat.

成功への近道ないんだよ

There are no shortcuts to success.

金のなる木はないんだよ

There’s no such thing as a money tree.

銀行にあんまりお金ないんだよ

I don't really have much money in the bank.

他に選択肢ないんだよ

There’s no other choice.

何も怖いことなんかないんだよ

There’s nothing to be afraid of.

最近は仕事がなかなかないんだよ

I haven't been able to find much work lately.

なんで冷蔵庫の中に食べ物がないんだよ

Why is there no food in the fridge?

悪気ないんだよ

I don't mean any harm.

その女は脈がないんだよ

That woman has no pulse.

— 自転車泥棒 (1948)

食べてる余裕ないんだよ

I don't have time to eat.

スーツケース置いた場所にないんだよ

My suitcase isn’t where I left it.