Answer:
it sounds like this person is going through a breakup? Either that or is in pain that her crush/ex lover is with another person. the person says, "the one who can touch the magic of your laughter but I know that laugh"
saying, the one who can touch the magic of your laughter, so would that mean that they used to be together, or the person is crushing on them, and is now the new one to touch her ex lover's/crush's laughter. But then she says she is the one who knows the laughter. So that makes me think that she might be his ex.
I think it must have been a breakup since it also states, "suddenly then on my lips, expires without force my joy, my tongue and like broken, and suddenly in the heart of my flesh, an invisible fire to slide my eyes no longer see anything clear". So she was happy but then in a split second was torn through pain. So pain from a breakup or being rejected? I think it is heartbreak.
Hope this helps tho!