The reason you become possessive is because you feel your self worth depends on your partner’s exclusive attention.
The moment you get some of this from other women (female friends, light flirts, etc) you become less desperate and feel more valued.
What your partner gives you is love and validation.
Now, the moment you realize you can get these from other sources, it empowers the way you stand in your relationship.
It is okay to have a light flirt.
It is okay to sometimes fantasize about other women.
It is okay to loosen up slightly the boundaries of your relationship and realize that there is a world out there.
Obsessive jealousy can be the result of isolation.
You isolate yourself and the relationship within a cocoon of energies.
What you want now is open up and connect.
Your partner stays number 1.
Being in a committed relationship must not stop you from interacting with the opposite sex.