How do I help my 18 yr old son get over embarresment?

Ok so not that long ago my son (he gets motion sickness) my other son, and my husband were on an 18 hour flight. My son was pale white so i knew he needed to get into the bathroom but both were busy. Since we were in the 1st row in first class he needed to throw up all the way in the back. He just barley made it and threw up in the last row before the bathroom (we took a midnight flight so only like a quarter of the plane was full) He got lucky and no one knew it was him. He went into the empty bathroom and acted like he just noticed the vomit. Then 3 other people got sick. He was so embarresed and we still had 13 hours to go. He thought he threw up everything in his stomach (thank god he didn't eat alot that day) He would hardly look at me the rest of the plane ride (he kept hiding his face with his hand) Plus the flight attendents were making comments about it so I think it made him feel worse. So I got him whatever he wanted (wet wash cloth, a blanket, water etc.) Thankfully he slept most of the flight. On the flight back I made sure he didn't vomit one bit and thank the lord he didn't. Not that much later his girlfriend wants him to go to Europe with her and he keeps refusing, but I think he should go (he loves his girlfriend and Europe is and amazing place to be). I don't blame him for being embarresed at all but it's stopping him from having fun and I know his girlfriend and she won't break up with him because of motion sickness. He already told her he get motion sickness I keep telling him to take dramamine and it'll be okay but he still doesn't wann go. So any advice on how to helo him get over it so he can have fun in Europe?