While they do not occur in all cases, physical symptoms such as anorexia and addiction to nicotine may appear in cases of co-dependency, notes Everyday Health. People who are co-dependent may also work, exercise or eat excessively.
Because they tend to get involved with people who are unreliable and needy, those who are co-dependent spend much of their time attending to others' needs and ignoring their own, states Everyday Health. Someone who is co-dependent may have an exaggerated sense of responsibility for others, an unhealthy dependence on relationships, suffer from poor self-esteem and experience fear of abandonment. While co-dependency was originally used to describe relationships in which one partner is an alcoholic, use of the term has evolved to include relationships in which drugs and alcohol are not factors.