"I am the only person who can kill an air plant!"
First, you're not. I have killed my fair share of plants -- air plants and potted. Spider plants and succulents. Perennials and annuals. IT HAPPENS!
The thing with plants is that you never know what might happen or why. The good thing about air plants is that the number one issue is easy to solve.
Root rot is the most common issue with air plants. Root rot can cause them to look dried out, to turn dark grey, or to fall apart. Root rot happens when water gets trapped in the base of your plant. The best way to avoid it is to turn your plant upside down after you water it. THAT'S IT! Soak your plant and leave it upside down to dry.
If you truly have a black thumb, no worries. Air plants take longer to die than other plant types:)