Translation - Turkish-English - Dün neden öyle davrandığını anlamadım. Bu yüzden...

Hi cheesecake,

"reacted a lot" is not that usual...perhaps "had such a reaction" ? And it should be a period or a comma after that.

"I didn't have to see the behaviour that you did" what about:
"I shouldn't have seen that bad behaviour from you"?

don't repeat it again ---> don't do it again

("repeat" already means "do sth again/once more" )

Hi lilian, you are right thank you for the explanation.

But in my opinion, the sentence starting with "I didn't have to.." should be editted a little more different. Because she means there "I also saw the behaviour that you did to your friend, but I was not obliged to see it/ I wasn't supposed to see it." So we might say "I was not obliged to see that behaviour from you." What do you think?

"I was not supposed..." would be fine

OK done!

behaved like that yesterday....>behaved like yesterday
such a reaction....> such a big reaction

Thank you merdogan. I guess I should have also add "such a big/great reaction" or even maybe "such an overreaction." Could we edit the sentence like this please lilian?