I feel you, LinusK. It's been about 8 years ago by now since I sent my son across the country to go to school at Berkeley. That was the first time he had flown without either me or his dad. So it's not just about the flight, it's also about not being able to help them navigate things once they get to their destination. He's a sweetheart, but he cautioned me about being too emotional at the airport because he didn't want to become emotional. I sucked it up as I waved good bye.
A few years later, he had a great opportunity to study abroad in London. I was better that time. He loved living in London so much that he sent me a plane ticket so I could go visit him. We had a great time together.
Being a parent is fraught with so many "what ifs." You just gotta have faith that everything will work out, and everyone will be better for taking whatever risks it takes to achieve their dreams.