Lack of interest
One important give-out sign in depression is how depressed individuals often lose interest in everything around them. This is even more noticeable in major depression, when patients may even lose interest in their own hobbies and passions. They stop enjoying those activities that used to make them happy, and it is often a difference that friends, parents, and other relatives realize early enough. During mourning, people can often feel this lack of interest as well, but it has more clinical relevance when it gets prolonged in time and starts affecting the social and working environment of the patients.