In the first stage of this obsession, the person is instantly drawn to the other. S/he begins to fantasize about the relationship with the person. It is also at this stage that that one begins to exhibit obsessive tendencies.
If the person manages to get into a relationship with the object of their obsession, the disorder proceeds to the second stage (if not, then the person might go into depression or in severe cases, take an extreme step)
A person suffering from obsessive love disorder is very insecure about his/her relationship. Baseless thoughts of abandonment dominate their thinking. There is a need to be constantly in touch with one’s partner, whether through calls emails or messages. There are unrealistic expectations from the relationship, like spending every free minute together.
At some point, the partner refuses to meet these demands and the disorder proceeds to the next stage. The person might start keeping tabs on his/her partner, by going through their emails or diaries. S/he might even drive around the partner’s residence or place of work to make they are where they are supposed to be.
S/He may demand explanations or detailed analysis about his day-to-day activities. There might be refusal to understand the partner’s needs to socialize with others as well. Any interaction with the opposite sex is not taken kindly and can lead to unfounded accusations of cheating.
At this point, most partners understandably flee from the relationship. This can be the most dangerous stage, as feeling of rejection runs very high. The person may start stalking or harassing the partner. In extreme cases, there have been incidences of murder and rape. There have been numerous cases of suicide.
So what causes the dent in the attraction-to-companionship stage that most relationships go through? The answer may well lie in the childhood. Being neglected or criticized by parents can lead to low self-esteem and feelings of inadequacy in a person.
The need to be loved gets very high and the person starts building a fantasy world where s/he is very much wanted and desired. When the child grows into an adult, s/he expects his/her partner to be as perfect as this fantasy world, leading to unrealistic expectations and obsession.