Remember that all of this is just feelings

Both men and women can become possessive in relationships, often to the detriment of the union. Ironically, the more possessive a person becomes, the more their partner will likely struggle to be free, hence making the person feel an even greater need to control the situation. It is a vicious and emotionally draining situation.
The driving force behind possessiveness, in both men and women, is insecurity. People who are self-confident and happy with themselves typically have faith that their partner will love them too, and don't feel a need to control the relationship or their partner.
Conversely, someone who is insecure may doubt their partner's dedication and may therefore try to maintain control of them. In short, they are feeling vulnerable and will do anything to make sure they are not hurt.
"Feeling possessiveness toward another is based on feelings of scarcity and insecurity," points out Hale Dwoskin, CEO and director of training of Sedona Training Associates.
This insecurity can stem from a number of places: a parent leaving you as a child, a past romantic partner who was unfaithful, and more.
Possessiveness also often stems from feelings of jealously, and fear that a partner does not love them.
According to some researchers, jealousy is actually a part of evolution. They say that men tend to be more jealous about their mate being sexually unfaithful, while women get more jealous about emotional infidelity.
The reasoning is that men want to know that their genes, not another man's, are going to be passed on, while women traditionally needed to maintain a man's emotional love in order to receive shelter and protection.
Nowadays, some of this evolutional jealousy may still be at play, while other factors (such as a person being cheated on or abandoned in the past) almost assuredly also play a role.
Are You, or Your Partner, Too Possessive?
If you are in a relationship with someone possessive to the point that you are fearful of your safety, you should seek help immediately.
If you recognize that you or your partner is just a little bit possessive, realize that feeling a little possessive or jealous is quite normal, but if it gets excessive the relationship is at risk. What can you do? The following tips can help you get rid of your possessive feelings, or deal with a possessive partner, so your relationship can flourish:

1. Identify the reasons why you're feeling possessive. Most likely, it is YOUR issue (such as a fear of abandonment) that is making you possessive and is not related to your partner at all.

2. Let go of your fear and insecurity. If you have possessive tendencies, you need to learn how to boost your self-esteem. The Sedona Method can help you to do this by teaching you how to release negative feelings about yourself along with fears of infidelity.

3. Be true to yourself. If your partner is overly possessive, don't stop doing the things you love to appease him or her. You can verbally reassure your partner of your dedication to the relationship, but you should under no circumstances give up your own interests because of it.

4. Release your desire to hang on, or pull away. Part of the cycle that keeps a possessive relationship so tumultuous is that as one partner tightens his or her grasp, the other increasingly pulls away. If you both let go of your need to control, or your feelings of "pulling away," there will be much less fuel to fan the fire.

5.Reaffirm your love. Sometimes all a person needs to get over a possessive or jealous nature is reassurance that they're loved. Taking the time to rekindle the love in your relationship will increase your overall happiness and peace of mind.

6. Remember that all of this is just feelings. "When someone is chasing you it can make you feel like running away," Dwoskin says. "Remember, this is a feeling, not the truth." The more that you and your partner focus on letting go of your negative feelings about the relationship using The Sedona Method, the easier it will become to feel secure in your love and devotion, without a need to control it.