I also work out while in Negril, it keeps me on track so I can indulge a little more than usual and not gain weight, but mostly I just can't go many days without strenuous exercise as I start to feel poorly. I have been a "workout person" for around 14 months now and it is a permanent lifestyle for me as the benefits have been just incredible. I think you can totally maintain your program while there with the planning you're doing. I agree with the suggestions to talk to your trainer about designing a vacation workout, specifically one that you can do anywhere without equipment (or using some resistance bands that weigh almost nothing and you can take with you) in case you don't feel like going to the gym on some days. The more consistent you are in the early stages, the more quickly you will reach the point of exercise becoming routine for you, which I found to be a major turning point in my life.

My biggest challenge in Jamaica is sugar intake because of fruit, fruit juices, and alcoholic beverages. One of my tricks is to mix my fruit juices/rum drinks with just a bit of juice and some of that awesome Everess club soda, which is super sparkly. Since I don't normally have much sugar, my spritzer juices are just the right amount of sweet with much less fructose. I also try to request vegetables instead of rice an' peas for several restaurant meals. I know you do a lot of your own cooking, so that won't be as much of an issue.