Your dog is your best friend. However we cannot be around them all the time. We have obligations such as a job. This may mean that your dog will be left alone in your apartment or house. Your dog will have to deal with this, but he or she will not like this. They will find different ways to deal with this lack of attention.
Lets face it your dog is going to miss you. They actually love you more than you can understand. They will have deal with separation anxiety. Because of this separation anxiety they might destroy stuff or howl when you are gone. However this type of behavior is not acceptable. As the more intelligent creature you will need to train your best friend to deal with your separation with them. This will require some research and patience.