If you're blissfully happy, you're rapturous. You could describe your purring cat rolling around in catnip as rapturous.
The adjective rapturous is great for describing someone who's delighted, like the rapturous excitement of a room full of teenagers at their favorite pop star's concert, or the rapturous look on a child's face when she opens her birthday present and finds exactly what she had hoped for. The root word of rapturous is the Latin raptus or "a carrying off," and until the mid-1600s, that's exactly what rapture was used to mean.