I hope you are doing as well as I am or even better. The picture isn't really true. There is no snow in Heidelberg this winter. But Christmastime, with or without snow, is always a nice time and in particular a time to think of/about people. And I'm thinking of/about you.
I was really impressed by you and your words in S.

Be careful with 'fine.' If you use 'I'm fine' as an answer to the question 'How are you?', then it means 'Mir geht's gut.' So far, so good.

But if you use 'I am fine' to describe yourself, in casual language it can mean 'Ich bin prächtig / guuut / usw.' That sounds like boasting, so it probably isn't what you really want to say.

For that reason, as a statement it's usually better to say 'I'm doing well' or 'Everything is going well for me.'

One more tip: The abbreviation 'Xmas' has a capital letter and no hyphen.

But it's usually bad style anyway, so you should not use it in normal writing. It's correct only when you really need to save space, like on a sign or in a shorthand list.

just a few suggestionss:

to be fine, but not to be finer (better better);

drop the telling lies phrase (sounds a bit negative);

Christmas (no time here) is always a pretty nice time;

to think of s.o.;

you and what you said in S. really impressed me (why all passive?)

I want to write a Christmas card and it's very important for me that the card is written in correct English.
Could someone just read through the text whether it's correct.

Ansonsten folge ich hm--us:
I hope you are doing as well as I am or even better. The picture isn't really true: There is no snow in Heidelberg this winter. But Christmastime, with or without snow, is always a nice time and in particular a time to think about people. And so I'm thinking about you. I was really impressed by you and your words in S.

Thank you very much. Your answers really help me.

Wow, I wasn't aware that Xmas is bad style. In Germany we always use it. You can see it really everywhere. Good to know that's not usual in English.

Well, it is pretty much accepted if it stands by itself, like in sale signs, but as with every abbrev. you should avioid it in full sentences.
;-)))

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