It IS SO HARD to leave them, isn't it!
We had booked and paid for a 2 week vacation, before we even thought about getting Rowdy. He was only 4 months old when we had to leave him. I worried so much about him. He stayed with my daughter who has 3 dogs herself and is a total dog NUT - but of course, I worried that she wouldn't know how to take care of him like me!
Of course, he did just fine and loves going to her house now - BUT if we leave him there, he does cry for a bit, but then he gets into playing with the other dogs and he has a great time. When we pick him up, he sticks to us like GLUE!!!
Both my husband and I have to travel some, but usually not together so one of us is home with Rowdy. However, he has now figured out the suitcase routine and when we get them out, he gets in them and sits and sits and sits - like "ya'll aren't getting out of here without me"!
He will even sit on top of the suitcase, after we close it up!
We planned our vacation this year so that he can go with us. We are going to fly to San Francisco, rent a car and drive to Portland, OR where I have a weekend conference. We decided he could come along and we are all going to have a great time!!!
Good luck and have a good time on your trip - everyone has given you wonderful suggestions!