Isn't that contradictory? Jealousy is wanting what you don't have, and possessiveness is wanting to keep what you already have. Which should be shunned in your mind?
I agree with you, my statement was a joke about those who wants others to share their SO, I think wanting to keep a intimate relationship private is healthy and fine.
A man can be envious of another mans wife, and a man can feel jealousy when his wife is spending time with another man, of the two I think envy is the destructive mindset/feeling.