Translation:Ben senden daha üzgünüm.
You may omit "daha" in some sentences, if not all, since "-den/-dan" also gives the meaning of "daha". In this sentence, I would use "daha", to make it clearer; but also without it, the sentence still gives the meaning. Some examples:
"O benden (daha) güzel."
"Sen ondan (daha) çalışkansın."
Çok teşekkür ederim! :-) Is there a particular rule that explains when we should use 'daha' and when we can omit it?
Rica ederim :)
Well, I don't remember a rule, and in all the examples I can think of; yes you can omit it. It is optional.
I would be glad, if Alex or Selcen could confirm me though :)