At least you don't have to go to the BOONIES of NORTH CAROLINA to spend a week with a mother-in-law who HATES you!!
I consider you pretty lucky
You'll have fun and it will be great bonding for you and your man.
About him being a little worried about you leaving, I can completely relate. I was in a really bad relationship for three years before meeting my wonderful husband, and my ex would frequently go out and do stuff that should not be done while in a relationship. I used to be OK with being left alone for a bit, but after a few years of that crap I became so insecure about it. Even though my hubby is 180% different than the ex, I still have major issues with some things. It's just me. I imagine it will continue to change, but I think it will take a long time. I wonder if something happened in his past to make him a little insecure?
Well, good luck and have fun!! He will love you even more for it!