Hi Shez. I'm often away for three months at a time and travelling is not too much trouble if you plan carefully. I'm usually staying at the same place when I'm away though, so insulin deterioration is not really a problem as I just put it in the fridge when I arrive at my destination. Don't forget that it's the total time out of the fridge that matters i.e. if its only out of a fridge for a few hours between destinations, but it's still in a fridge for most of the time, it should keep its potency for several months. Every hotel that I have ever stayed at has been very cooperative for putting the insulin in their kitchen fridge, but I did leave it behind on one occasion!
Airlines will allow you an extra piece of hand luggage for medical reasons. So I calculate my anticipated consumption of insulin/infusion sets/cannulas/lancets/test strips/pills/etc etc before I go, add at least 50%, and put the whole lot in a holdall that stays with me all the time. My PCT provided me with a back-up pump for emergencies, and that goes in the holdall as well. Provided the back-up pump is not powered up it's safe to go through the airport X-ray scanner in the holdall, but you mustn't let your pump go through the scanner. I usually indicate to the security guys that I am wearing the pump and they do a regular frisk. I've never had any hassle with airport security (yet!). Oh, and ask your DSN for a covering letter to show to any jobs-worth, and take a copy of your usual prescription.
I guess it would be prudent to check availability of your particular insulin in the countries you're proposing to visit.
The most important tip: have a good time and relax - if you have a problem (like leaving your insulin in a hotel fridge) you'll deal with it.