I think you interpreted it (uh-oh!) transferentially.
PAST: Parent forgot and didn't care, didn't follow through on promise. You suffered.
PRESENT: T forgets, BUT DOES care, and DOES follow through on promise. Now - your first impulse is to react to T's forgetting and to suffer, **, but then can you accept T's caring and the actual act? And also "process" some feelings at **! Easy-peasy, right? Not! (And we think T's "just sit there"! :grin) But yeah, your interpretation was correct - you keyed in on the forgetting being the issue, on what was causing you pain, on what was special to you in an odd way, on what stuck out.
But it's the what forgetting MEANS, not just getting the other person not to forget anymore.

I ONCE complained to my 2nd husband that one of the reasons I divorced my 1st husband was because he wouldn't go to foreign films with me (while yes I went to every new Clint Eastwood movie with him!). So husband No2 dragged me to every French film in a 40-mile radius. But that doesn't fix the basic problem, right?