Informal letter

Hi, my Dear friend!
I'm glad to write you this letter! How is your life going on? You asked me to tell you about my best friend. I will do this with enjoy!
My intimate friend is Monika. We've met since our childhood. We played together and it was interesting! And up to now we are friends.
Monika is very loyal and dedicated. I always can trust her. She gives me some advise, supporting me in the difficult situations. But we always try to have fun, enjoying life.
Well, that's all my news for now. Let me know about your plans. What are you going to do in your winter holidays? Do you want to stay at home or travel to anywher? Who will relax with you? And my summer holidays will be not soon. That's a pity! But I hope we can meet with each other another time, I look forward to it! Have a good time! Keep in touch! 
Yours, Elvina.

Informal letter

Hi, my Dear friend!
I'm glad to write you this letter! How is your life going on? You asked me to tell you about my best friend. I will do this with enjoy!
My intimate friend is Monika. We've met since our childhood. We played together and it was interesting! And up to now we are friends.
Monika is very loyal and dedicated. I always can trust her. She gives me some advise, supporting me in the difficult situations. But we always try to have fun, enjoying life.
Well, that's all my news for now. Let me know bout your plans. What are you going to do in your winter holidays? Do you want to stay at home or travel to any there? Who will relax with you? And my winter  holidays will be not soon. That's a pity! But I hope we can meet with each other another time, I look forward to it! Have a good time! Keep in touch! 
Yours, Elvina.