Where are you staying? Do you know if your hotel/accomodations has a mini fridge? I find having yoghurt or fruit on hand for breakfast if that is an option makes it easier. I generally aim to maintain on vacation rather than lose though since my schedule is not as "Set"
I just got back from vacation and we stayed at Candlewood suites-they have kitchenettes in the room (full fridge, stovetop, microwave, coffee maker, dishwasher). That helped a lot! When we went out to eat at PF Changs I just looked up the nutrition information.
I don't log calories, but I am mindful of my choices and portions. I also take nuts or protein bars for those times when there don't seem to be good options. An example - on the boardwalk last year, my family was all eating funnel cakes and shave ice - I got a few strawberries dipped in dark chocolate. Still a decadent treat for sure, but I didn't feel deprived and it was relatively low in cals. At restaurants I either split a meal with someone or take half to go. I also volunteered to take my nephew for long walks in the stroller so that helped with the activity.
This year I am going on a cruise. I am setting a goal to do some activity every day and really focus on only eating when I'm hungry.
Lost 135 lb in 2011-2012. Regained 40 in 2013-2014. Back in the saddle again...