People are social creatures by nature. They are born into families and being a member of a family is their natural state. Most people live and work with other people and are, in varying ways, dependent upon them for their livelihood and their life. Other people are, in turn, dependent on them. People depend on one another to meet the basic necessities of life, including food, clothing, shelter and safety needs. They need access to the paycheck that pays the rent and buys the food, they need protection from common enemies, and they also need assurances that they will be cared for should they fall ill. They depend on each other to meet sexual and reproductive needs. They also need to belong to groups of other people (e.g., their family of origin, the family they build with a spouse, a tribe, a culture, a work group, a religion, a nation) in order to define themselves as people; to form healthy identities. Such belonging needs become primary to most people as soon as their more basic and safety needs are attended to. Group membership even figures into "higher" sorts of needs, such as people's need for achievement and status; there is no achievement or status except in relationship to others. Relationships are so important to human health, that it is in fact, unthinkable that a person could be healthy without them.
Though relationships are a vital and necessary part of the human condition, it is frequently quite painful to need other people. There are essentially two different kinds of relationship problems. Either people do not have sufficient relationships (or sufficient quality of relationships), or they have relationships, but those relationships are conflicted in some manner so that they don't satisfy, or are a source of pain. People feel lonely when the relationships they crave are not available to them. As painful as it can be to be lonely, it is sometimes balanced out by another pain - the pain caused by fear of rejection that some people feel when they think about pursuing new relationships. People who are in relationships are not immune either. Some relationships end painfully. Some end up being abusive, while others simply don't measure up to people's varying needs and hopes, or somehow fail to provide a nutrient necessary for keeping the relationship alive. Some people stay in such relationships and make due with their pain, while others leave and face a different sort of difficulty; that of finding new relationships that will work out better. Even healthy, caring and supportive relationships have moments of tension that are distinctly uncomfortable. Though some relationships are undoubtedly healthier and better to be in than others, there is no such thing as a perfect pain-free relationship.
Creating Satisfying Relationships
Some people have an easier time forming and maintaining satisfying relationships than do others. It is true, in small part, that differences in physical appearance, wealth and social status account for some of this ease (there is no shortage of people who want to be with others who are attractive, well off or famous), but there are also many, many people who aren't particularly attractive, rich or famous who still enjoy numerous satisfying relationships. What sets these regular satisfied types apart from other less-satisfied people are their mastery of social skills.