I know it's hard, but please ignore jealous people, and concentrate on being the best person, and the best friend you can be. If other people want to be jealous idiots, then that's their problem. I'm afraid we can't stop them being like that.
I used to be jealous of celebrities like Princess Diana etc. She was so beautiful and kind, just how I would have loved to have been. However her tragic fate was so terrible, obviously I realise now that my jealousy was a complete waste of time.
If you are a hard worker, you will reap the rewards later on, for example when it comes to the job market. And if you are kind to others, you will get a reputation as a great team player. This will take you even further up the greasy pole of success.
Good luck, and keep on being great.