Yes, clearly stationery, and with a poignantly depicted message that rends the heart! Colors, shapes, and subject matter are well composed and understood.
Nice. I would consider cropping tighter to remove the black in the corner - it feels like it draws my eye from the subject matter and remaining composition.
The lighting is well done. I would remove the envelope on the left hand side, as it tends to draw attention away from the message. I would also move the loose petal from underneath the rose and place it somewhere in the blank white space a little to the left of its current position. The brown leaf on the right doesn't really fit this image either.
Now this is very pretty English stationary. I have china plates with the English Rose design. They are so pretty and this image reminds me so much of that.