The fact that you're admitting this is a wonderful start. I think everyone does this to an extent. I know I do sometimes
But try and remember that it's good for your humility to remember that you're not the best at things. But more importantly, that God loves you just the way you are, and He's given you your talents and graces as a gift for you to help you to be the person He wants you to be.
Someone once suggested to me that when you feel jealous at someone's achievements, try and go so far the other side that you overcome it. The example he gave was that he'd just started at uni, and as a pretty good musician he thought he'd have no problems in getting into orchestras and ensembles, but unfortunately that year didn't really get into any of the ones he wanted. A friend on his corridor had got the lead part in the freshers play and initially he was jealous, but then he went out and bought a big cake to help her celebrate, and then he didn't feel so bad about what had happened to him. I did a similar thing at results time at uni last year, I failed my dissertation, and therefore was awarded an unclassified degree, whilst a ridiculous number of my friends had got 1sts (stupid scientists
). In my room I had a bottle of champagne which I'd been waiting for a good excuse to open, and kept forgetting at events like my birthday or Christmas, so decided to open it to celebrate them. Whilst it didn't entirely make the jealousy go away, it certainly helped and I had a great evening, which otherwise I would probably have spent hiding in my room.
I feel like I've just rambled a huge amount, so apologies if it doesn't make much sense