" Intimate, or emotional, loneliness is the longing for a close confidante or intimate partner—someone with whom you share a deep mutual bond of affection and trust. Relational, or social, loneliness is the yearning for quality friendships and social companionship and support. Collective loneliness is the hunger for a network or community of people who share your sense of purpose and interests. These three dimensions together reflect the full range of high-quality social connections that humans need in order to thrive. The lack of relationships in any of these dimensions can make us lonely, which helps to explain why we may have a supportive marriage yet still feel lonely for friends and community. "

― Vivek H. Murthy , Together: Why Social Connection Holds the Key to Better Health, Higher Performance, and Greater Happiness