There will be a time in your life where you will constantly hear, "I got the job/internship!" or "I was accepted to XYZ!". It will feel like everyone around you is succeeding while you remain stuck with nothing new to tell.
Many of us are in that stage where we will soon spread our wings and fly, but what if the weight of your situations is constantly bringing you down? You have to take a minute and realize some things...
The times that you've been rejected are meant to make you realize that those who rejected you did you a favor. It could either be that you are not the best fit for them and they are looking for someone who is more experienced, or they simply want to advise you to reach for smaller things that will prepare you for the big things.
You have to realize that when you are told "no" you need to keep going. The closed doors aren't a way to make you stop, but rather to keep you on the right path so you will gain knowledge of how life works.
Sitting and hoping for the opportunities to come to you is simply unrealistic. If you want something bad enough, you have to go get it even if it means stepping out of your comfort zone. And that's the point.
There are many celebrities out there who have been told "no" and had the doors shut in their face, and if they have never gotten back up they wouldn't be where they are today.
Like Ralph Waldo Emerson once said, "Imitation is suicide". Quit trying to follow the crowd and quit comparing yourself to other people. We have all been built differently and part of this building-of-self requires different building blocks.
You can't force certain puzzle pieces to fit with each other, because they were meant to be different for a reason. They were meant to fit with the other part that was made for them.
Don't let the closed doors get you down, something out there is being prepared especially for you. While you wait, work on what needs to be worked on and have the patience for the things to come.
Thank the closed doors because, without them, you would find yourself in a sticky situation and perhaps things would have gone worse. Wait for what's meant for you and work hard to become a better version of yourself each and every day.