I think we've all been jealous of someone at some point in our life, but comparing ourselves isn't fair to anyone.
When I start to feel a little envious of someone, I always try to take a Biblical stance on my feelings. I know that God didn't create me or you to be like anyone else. We each come into this world with an individual plan and purpose for our lives, and I think once we can tap into that and figure out what that is, we grow into ourselves and can start to relieve some of that pressure.
Also, may be the issue of low self-esteem and distorted image of one's worth. If we feel like we're falling short in some area in our life, we need to make the effort to improve in those areas so we can become more comfortable when in relation to others.