ותאמר ציון עזבני ה' וה' שכחני ... (ישעי' מט-יד)
Yeshaya HaNavi describes the feeling of despair within the Jewish people in the aftermath of the Churban where they lament the feelings of abandonment that the very earth of Eretz Yisroel feels; “Tziyon says, Hashem has forsaken me … Hashem has forgotten me.” But while Hashem does answer them that He “could never forget” them (Yeshaya 49:15), the question of abandonment still remains.
R’ Hersh Domaluk shlit”a explains that we often conflate the feelings of abandonment with feelings of being forgotten. However, it is important to separate those two since they are two distinct feelings. Chazal explain that being abandoned can hurt a person tremendously, but it is no match for the pain associated with feeling forgotten. This is because when a person is abandoned, the possibility still exists for the abandoning party to harbor feelings for the person they had forsaken - thereby keeping the prospect of that person being brought back still alive. But a forgotten person is just that - forgotten and discarded - with almost no hope left to be remembered or returned.
So, while Hashem allowed Eretz Yisroel to be ransacked and the Bais HaMikdash to be destroyed - effectively abandoning the land and its people and sending them into exile in a foreign land - He nevertheless offered a glimpse of solace in that He promises that He has never and will never, ever forget His children - the Jewish people - and they will surely be brought back home.