If you scroll down this link (Tripadvisor Crete) you can click on foods from many countries other than Greece.
http://www.tripadvisor.co.uk/Restaurants...
If you not like Greek food there's nothing better than just switching to Italian which is nearly always available in most resorts in Greece and very much so in cities like Athens.
Italian restaurants Crete
https://www.google.co.uk/#q=italian+rest...
Italian restaurants in Athens
https://www.google.co.uk/#q=italian+rest...
You'll also find lots of other non-Greek restaurants too- esp in Athens and Greek resorts.
Have a great time in Greece
https://www.youtube.com/watch?v=0T7YvNCBkXA
London UK
There are usually plenty of choices of non-greek food on most menus , as well as pizza places , and McFood outlets ( the Greek national chain is called " Goodys " and is very like McVomits in the range of synthetic crap it supplies to the public ) so you should not have to starve .
And you can shop for food at all the local mini supermarkets too , so actually , you dont really need to eat anything " Greek " during your entire trip , if you didn't want to .
You will have no problem. Depending the place you will be in Crete you may be able to find also English food, but it will a shame not to try the local dishes, which in most cases you can see and decide if they will be to your liking. Besides Creatan dishes are considered to be the most healthy in Europe.
In Athens you will have no problem at all.
I know in Athens there are a lot of restaurants that aren't greek but even some greek restaurants have other types of food btw. <3
Well that's unfortunate. You can find McDonald's, Pizza hut etc in Greece so that shouldn't be an issue.
So go to Turkey. Anything you want can be obtained there
MONG