You are what you think
Have you ever thought about what makes you sad or happy? Can you influence what you feel about different situations? You can.
In his book "As a man thinketh", David Allan talks about how situations always end up how you think about it. Did you thought that a certain project won’t work? It probably won't work as a consequence. And if it doesn't, why do you feel bad about it? Of course it sucks that it failed but can you change it? No, but you can change the emotion you feel while failing. Understanding this this helps a lot.
"A man is literally what he thinks, his character being the complete sum of all his thoughts."
Happy or sad, curious or bored, it all depends on your thoughts. So changing the way you think about things and situations can be very beneficial to yourself. You should start to be proactive. If you can't change it why bother? Being proactive means that you should focus your attention on things that you can actively affect.
It all focuses on the belief that you create your own environment. Not forced upon you without an opportunity to control it. Being proactive gives you a feeling of control. Also being proactive involves taking responsibility on your actions, always keeping in mind that you can influence the outcome by your actions, going hand in hand with the mindset of "life-long learning". The art of constantly trying to improve yourself.
That said, being proactive can be very beneficial while traveling. If something doesn't work out as you would like, try focusing on the solution, not the problem itself. The first step for me was, believe it or not, not complaining about the weather. Just try it. If that's successful try to reduce the amount of bad news you watch.
A good example for this is the "Pray for Paris" Facebook event. You could customize your profile picture with the colors of the flag from France. No shame on you if you did it. But think about it this way. I assume that you didn't know anyone of the victims. If no one had told you there were deaths in Paris why would you bother? This sounds hard but just by reducing the amount of bad news you consume you will profit heavily. Also, think of all the free time you will have.
While traveling try to think positive as much as possible. Always think of the lessons you will take with you. Learning out of failures and apply the things you learned to your future life. Step by step you will find that life itself is a learning process that never stops.