It's terrifying. You can only go through so many times of being knocked down, tossed aside, ghosted, disappointed, before you just want to give it up. And hey... in case no one has told you, you can take a break. You have every right to some "me" time, in fact, it's damn healthy. I highly recommend it.
But when you do meet someone that you see potential in, please don't run. For a few reasons.
One reason being, you deserve to be happy. And you can be happy without another human being, and your happiness most definitely should not be dependent on another human being. But if someone cares about you, shows genuine interest in you as a person, and makes an effort, hold tight and give it all you've got. Fate works in mysterious ways, and it's not always going to wait until things are convenient for you.
Another reason being, running off because you are afraid of a good thing is ridiculous. You may think you are doing the other person a favor, but you're not. What you're doing is making them question why they're not good enough, what they did wrong... you've been there yourself, haven't you? Gave something your very best and watched it turn to dust, and you never could figure out why.
Which takes us right back to the beginning: learn to open your heart again. Please.
You are not doing yourself ANY favors by putting up walls that cannot be taken down. Opening up to another is always a risk, but the biggest risk of all is not taking one. Every chance is worth taking. You will learn and grow, no matter the outcome.
Keep the faith.