I'm glad you answered my messages. I understand you are busy, I am happy to write to you, you are a good friend for me. I don't want to lose a good friend like you.
I'm glad you got my message. I understand you're busy, I'm happy to write to you. You are a good friend to me. I do not want to lose a good friend like you.
I'm glad you reply my message. I understand you so busy I am very happy to write to you. You've been a good friend to me. I don't want to lose a good friend like you.