I believe that what you are describing is actually envy.
Jealousy is a resentment against a rival-or enemy.
Envy is wanting what someone else has.
I kind of think of it as jealousy is when I don't want someone else to have it period.
But envy is when I don't have it and they do and I want it too.
If that makes sense?
And to your thought-
Yes, I agree. I don't tend to be possessive or jealous by nature. However, I do find that it is harder when I want something and someone else has it but I can't.
On the other hand, if all of my needs are fulfilled, I can fully enjoy seeing them enjoy all sorts of things without any negative feelings erupting.