Armures literally translates to "armors". It's a powerful, visual word that you don't typically hear in a pop song, making it especially memorable.
In this poignant ballad, Louane uses it metaphorically to talk about emotional defenses. She sings, "Les fous c'est fait pour faire fondre les armures" (Crazy people are made to melt armors), suggesting that raw emotion and vulnerability have the power to break down the walls people build around their hearts.
This song is a beautiful and direct conversation with someone who has passed away. Louane sings about how everyday things, like being in a car or hearing a song, can trigger memories of this person. She calls unanswered questions "le pire" [the worst], and the whole song is full of them. She asks the person she's lost, "Est-ce que tu m'entends? Est-ce que tu me vois?" [Can you hear me? Can you see me?], wondering what they would say or do if they were still here.
She admits to having "conversations imaginaires / Avec des gens qui ne sont pas sur la terre" [imaginary conversations / With people who are not on earth] as a way to cope with her pain. It's a really honest look at grief. She doesn't care if people think she's crazy for believing this person is still close by. In fact, she suggests that being a little bit crazy is what helps break down our defenses and allows us to feel things deeply, like when a song makes you cry in the car.