I get stressed with travel as well. I try to over prepare...packing a lot of extra underwear, double check that I have all my meds and take a couple of extra days supply. If staying with family I will take Ensure in case I can't eat, or scope out a nearby grocery store so I can buy it. I take all my own snacks when flying, so I know I have things that won't upset my guts.
My last big trip I ate only my safe foods or liquid diet leading up to it, to make sure I didn't upset anything before. The trip prior to that I went into a flare right before from stressing, being busy with plans and eating crappy the weeks leading up to it.
Will you be traveling with friends or family? I can let my husband know I am not feeling well and he can divert attention from it...that's what makes me nervous - people asking a bunch of questions or becoming the center of attention. Helps to have someone you can team up with to help you or simply talk to.