is the use of zecher/remembering only for positive events?

Good Afternoon, I have been typing up old notes from one of my hagada classes from school and I came across something that I was hoping you can clarify for me. According to the Rabbi which I don’t want to say the name in case I maybe wrote this information down incorrectly and I do not want to incorrectly quote this Rabbi- we say zecher yeztiyat miztrayim and not on zecher being slaves in Egypt because zecher is usually focused on something positive. The question I had was then why do we say zecher amalek and zecher le chorbon? I tried looking this up with no success. I did see that there are many cases of zecher I did find that was positive like machazit hashekel etc I was hoping you would be able to help. Did I write this down wrong or is there something in these two seemingly negative events that would be a positive?Thank you for your help.

That's great that your'e so conscientious to clarify your old notes! In addition to the negative remembrances of Amalek, the Torah also tells us to remember Miriam’s speaking negatively about Moshe (Dvarim 24), as well as the sin of the golden calf (Dvarim 9). Apparently what your rav said was that when choosing between remembering the good and the bad, the stress is on the good (the mitzvah is called “to tell of the exodus from Egypt” and not called “to tell of the bondage”). Nevertheless we’re not naïve, and must also remember the hardships and challenges as well, which are an essential part of the growing and learning process. That’s why both Rav snd Shmuel agree that we start the haggada davka remembering something negative (!) and only afterwards, thank Hashem for the positive (Psachim 116a), they just disagree whether we’re talking about the spiritual redemption: paganism to monotheism, or the physical one: slavery to freedom).