rub it in

rub it in and rub sb's nose in it (mention something repeatedly to annoy; to keep referring to something that the hearer does not want to be reminded of, usually because it is embarrassing) — ткнуть кого-л. носом, тыкать носом (регулярно напоминая об ошибке или промахе); лишний раз напоминать (о промахе, ошибке, неприятности); напоминать о чем-либо неприятном, растравлять рану

Also rub sb's nose in in the dirt (to keep reminding someone about something they did wrong or failed to do, especially in order to punish them)

Don't rub it in. (контекст) — Не напоминай, (и так плохо); Не трави душу.

Example 1: OK, I know I made a big mistake, — you don't have to rub it in. Please don't keep mentioning it. (ecenglish.com)
Example 2: Don't say anything to Celia about Kevin getting the promotion instead of her. She feels bad about it, so don't rub it in. (ecenglish.com)
Example 3:I know I should have been more careful, but there's no need to keep rubbing it in. (LDOCE)
Example 4: I know I shouldn’t have paid that much for the poster – don’t rub it in, OK? (CACD)
Example 5: OK, I made a mistake - you don't have to rub it in. (CALD)

Related vocabulary:
rub salt into the wound
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