Does your dog react to fear from events they may have experienced in the past?
A very fearful dog may never be normal if they have been abused, that's why its so important in how you discipline your puppy growing up. So, keeping a realistic expectation can be very helpful and may help your dog improve in situations where your dog is nervous or skittish.
Keeping your dog comfortable and trying your best to minimize exposure to frightening situations. Providing a good diet, exercise and mental stimulation may help your dog deal with challenges they may encounter. The use of modification techniques known as desensitization and positive conditioning can treat all sorts of phobias, fears and anxiety disorders. You may even benefit from a certified behaviorist if fears are extreme.
Talking with your veterinarian about possible natural remedies could be helpful. Pheromones may help dogs feel more relaxed. If afraid from thunderstorms, there are wraps that can help keep a anxious dog calmer in that situation. No matter what has caused your dog to become fearful there are a number of treatments worth giving a try in helping your dog recover and possibly overcome the traumatic events they encountered in the past.