I feel sad when I'm leaving people and I feel terrible being left there on my own.

I agree. Having dropped off loved ones at the airport, the drive home is just as lonely as when I'm the one who is dropped off at the airport. Although, I feel like being the person who is not traveling gets slightly more lonely. At least when you're going somewhere new, you have something to look forward to. If you're just driving back home, you're going back to an empty home.

We are all transients here, coming and going, we are all equals. We entrust our lives to the airplanes. What lies ahead, we don't know yet. We can only enjoy our brief moments in the airport.

I feel this way about life for humans on this planet :)