Doctor Answers (1) on Over possessiveness
You have partly given the answer to your questions by saying that your overt possesiveness is causing turmoil in your relationship. Your anxieties and insecurities might be rooted in some of your experiences from the past or even your childhood. You need to discuss them in person with a Psychiatric professional so that they can brought to the fore and you can move ahead.
If you don't move past your insecurities you will have trouble sustaining relationships. Also you need to trust your partner. Strike a balance between your academic/professional life and your personal life. Do not make one thing the center of all your activities.