I'm afraid to let people in. Is there something wrong with me?

Okay, so where to start. Okay nvm i am 24 years old, i work as an event planner. I have never been in a relationship not once in my entire life. I'm not bragging, but i've been told that i'm pretty a million times and guys have been chasing after me. But the thing is, i dont feel like i'm good enough or pretty enough for anyone. I know that they say when someone loves you they will love you no matter how you look bla bla bla. But everytime i see myself in a relationship all i see is disappointment. I'm afraid that i will let the other person with my never ending flaws. Whenever a guy starts to start something with me. I will reject him and say to him its for his own good. Everytime i try to let someone in, this image of me getting heartbroken because i'm not good enough for him tears trough my mind. Even my friends have given up on me. Idk what to do, i know that there is not a single person who is perfect. But i just... idk.