Desert Roses with frost bite
How can l save my Desert Rose bush that has been affected with frost bite?
If only the leaves are damaged, but the roots are not damaged, the plant can probably recover. Is the plant in a pot that can be brought inside to protect it from future frosts? If so, trim off the damaged leaves and stems, and also reduce watering since the plant may not be able to use as much water now. Wear gloves while doing this, because this plant's sap is toxic and can irritate skin.
If your plant is outdoors, helping it go dormant by not watering or fertilizing it will help it protect itself from the cold.