There is only one question you need to ask yourself when feeling pangs of jealousy.

What am I afraid of?

Listen to your answers without censorship.

Then try writing positive affirmations about yourself. For instance , if you are afraid of not being loved , then write a positive statement about yourself saying:

I .....( insert your name here) deserve the best in life and deserve to be loved.

Write down the silent response you hear in your head to this statement.
Write down the original affirmation again followed by the silent response .

Keep this process going until the silent response becomes accepting.

This is a very powerful process. It takes time and commitment but it DOES work.
You may find out some difficult truths about yourself and the true state of your self esteem.

Good luck.
Jealousy can be overcome once you face your fears.