Dear Mark,

How are you going now?
Every country has its own culture and people have different way of life, so it's common that you have troubles as you mentioned in your letter. To help you, I have the following suggestions.

The old saying goes like"when you are in Rome, do as the Romans do". This just means if you are in a foreign country, you just follow the way of that country. So, it's good for you to learn the culture of the British and know something about their habit. I know that the British are very serious and they are not that open-minded, and they like to keep distance with others. But once you become friends with them, they are very easy-going and friendly and generous. Don't upset with your situation now. You will be fine soon.

I hope you have a good time in British.

Sincerely,
Tom