The only person who you should be competing against is yourself.
Realize that you have full control over your actions, thoughts, beliefs, values and emotions. Other people’s successes could be interpreted as a good thing; for example, you can be happy for someone finally achieving their dream, or contributing to something valuable.
But you can also use it to get depressed and tell yourself that you are a failure, and that you are worthless.
We don’t experience reality. We experience interpretations of reality. There are multiple filters that distort limited quantities of information that we perceive and then try to make sense of.
Your ego is trying to protect you by shutting down the voice that’s telling you how much you are actually worth. The lizard brain is afraid, and it’s going to make sure you’re ready to deal with the danger.
But there is no lion chasing you.
This is when your conscious mind comes into play. Emotional pathways are quick, but not very reliable. After this you need to consciously decide whether the danger is real.
In this case the danger is not immediate. So you’re left with the feeling of being inadequate.
But you have a choice. You can use that feeling as a warning sign and use it as a motivator to push yourself in the right direction, until you feel more confident.
In addition, you can use the other people’s successes to your advantage. Try to figure out what factors contributed to their success, and start modeling them. This will save you some time on trial and error.