Your work should be your motivation in the main. If you work with sick and in some cases unhealthy people who caused their own problems, you should be able to see what you must do, to not end up like that and as I said before, with your understanding of medicine, you should be in a prime position to get yourself into a better place.
You haven't put all the weight back on which is a good thing.
You should not be scared of your trip, that is a bit silly. Unless you're going somewhere where everything is deep fried, even the cereal, then you will be fine. You just need to make some common sense choices.
If something comes with a Cream sauce on, don't eat it, or request the sauce be left off. If you have something with dip on the side, leave it on the side. If something is called Caremalised, don't eat it, as it's Caremalised by using Sugar. Anything with a dough base, avoid it perhaps, unless the base was made with wheatgerm.
These are all examples to show you that this is not a massive test, it's just something you need to learn to conquor and you know you are capable, you just need to believe.
Keep doing what you were doing in January and you wil be fine, as long as you make sensible choices and don't get too carried away with the eating side of things. Being sensible about food WON'T spoil a holiday, unless you let it okay.

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