Summer of 2020 I went on a date with someone who lived several hours away. By the end of the date I knew I didn't want a relationship, but when they asked then-and-there to schedule the next one I chickened out and planned a second date. By March of 2021 our relationship had dissolved. In summer of 2021 I broke off what was left. Last week (2022 -- a year after I broke up with them) they sent me a letter that basically asks for an explanation. Three pages, hand-written in cursive.
In the letter my ex points out that the closeness I did not show to them, I did show to other friends. They were and are hurt that I didn't show that closeness to them.
My guess is this letter is less about closure (closure is something one can only give one's self) and more about them going through a rough spot emotionally. I care for their wellbeing and I hope they have an ever-better life. They deserve great things and great peace. I know that the letter is more about my ex not feeling loved by people in their life right now, and I feel strongly for them in that regard.
Since if I were to give an explanation (namely, that I don't share their feelings and that's why I broke it off) I would only hurt them and since I gave this exact explanation a year ago and they still want to know why (what it says on the tin), should I respond? Should I block them on social medias? What would I say in a response letter?