There is a legion of evidence now showing that people who are able to build and maintain close, supportive relationships tend to have less illness and live longer than people who either cannot maintain close supportive relationships or who have unsupportive or conflict-ridden relationships.
A long line of research into this phenomenon and theories of human attachment have shown that patterns laid down in childhood tend to permeate later adult life. Largely it has been found that children who have supportive and responsive parents tend to develop a sense of emotional security that not only lasts for the individual's entire life but also predicts whether or not they are likely to form secure, close and supportive relationships themselves.
Likewise people who grow up in a less secure and unsupportive environment tend to suffer from a range of attachment problems, like a fear of rejection, abandonment, tend to trust less, commit less and often find themselves either unable or unwilling to form close relationships with others, or they collude or find themselves in unsupportive and/or conflict ridden relationships later in life. Now obviously there is a range here from people with mild attachment, rejection and commitment problems to people with chronic issues. It has been found that people with high attachment anxiety have a tendency to worry about rejection and abandonment, use self-defeating or 'hyperactivating' coping strategies, and tend to focus on negative events and hold on the stress far more than people without attachment anxieties or in supportive relationships.
More recent research findings have found a host of health issues associated with relationship and attachment issues. These range from the physical issues such as cold sores, a range of stress related illnesses and even cancer through to stress, heightened levels of anxiety and depressive problems and include lower levels of ability to regulate their own emotions, which only exacerbates the issue.
A study just published by researchers from the University of Texas, Anderson Cancer Center, The Ohio State University College of Medicine and the United States National Cancer Institute has found one of the reasons for higher mortality and illness rates with people in unsupportive or conflict ridden relationships.
The researchers looked at the effectiveness of individuals' immune systems to see whether there was a correlation with levels of attachment anxiety. What they discovered was a clear relationship between the level of attachment anxiety of an individual and the effectiveness of their immune system. What they found was that the higher the levels of attachment anxiety an individual had the less effective that individual's immune system was.
Now whilst many people keep the same patterns of anxiety and fear of rejection and abandonment throughout their lives, it is very possible to change these patterns and change the nature of not just the relationships they have or attract but also improve their general health and, it would appear, repair their immune systems at the same time.
Fagundes, C.P. etal (2014) Attachment Anxiety is Related to Epstein-Barr Virus Latency. Brain, Behavior, and Immunity (2014), doi: http:// dx.doi.org/10.1016/j.bbi.2014.04.002