You will also be faced with a lot of time alone, away from your family and friends. I'm afraid there isn't much advice I can give you regarding how to handle this. Everyone is different when it comes to dealing with these things.
The only thing I can really say is to learn to enjoy being alone. Get into whatever interests you – reading, video games, movies...whatever. But find a way to enjoy your time alone or you're going to have a very tough time of things.
There are much better ways to stay close with people now than there ever were. Email, cell phones, and digital pictures and video can all help keep you closer with family and friends. If you're the type that shies away from technology – learn to use a laptop. It's not nearly as difficult as people make it out to be in their heads. Sharing pictures, video, and sending emails are all things that a 3rd grader can do.
You'll have plenty of time alone...take some of it to learn to use computers. It will quickly become a centerpiece of your daily life on the road and you won't be able to live without it ever again. Believe me.
Lastly, I think one of the most important things that helped me relax and deal with the everyday difficulties on the road was what I called having a 'shit happens' column. Almost everything that happens can be categorized in one way or another – and sometimes there's no other way to explain something other than to say 'shit happens'. You will get traffic tickets once in a while. Your truck will break down once in a while. Your dispatcher will make a mistake or a customer won't be able to load or unload you on your scheduled day. You'll get a cold or flu once in a while. A huge snowstorm will come through right when you're on your way home. Traffic will come to a standstill because of a huge accident on the highway and you're only 5 miles from your delivery with 20 minutes to spare.
All of the things that make you say “you've GOTTA be kidding me” - they will happen every once in a while - I promise you. Keep the big picture in mind. Remember, you still have your family and friends, you still have your career, there are other drivers on the road counting on you to do your job safely, there will be other loads, and there will be better times ahead.
If you can learn to shrug things off once in a while and just realize that 'shit happens' and it's not the end of the world then you'll be much happier for sure. You can't get all distressed and totally bent out of shape every time you make a small mistake or have a bit of bad luck. Relax, be patient, and try to roll with things. Sometimes the only other choice is to freak out, and what good does that ever do?
Shit happens...expect it and keep your cool.
In the end, I think you'll see that learning to drive a truck and learning to deal with the everyday stresses that come with driving for a living are equally important. If you can handle one well but not the other, your career will be a very short one.
Always keep the big picture in mind and anytime you consider taking a risk, ask yourself “what am I gaining vs. what am I risking by doing this?” If you look closely and consider things carefully you'll have a much better chance of avoiding problems, avoiding mistakes, and having a long, safe, enjoyable career.