Ahaha yeah, it seems like this game is difficult for people to get through. Keep in mind that the characters react differently to different teas. For instance, the character on the left really loves the catnip chamomile tea and it makes her feel good, but if you want her to talk about uncomfortable things that may not be a good thing!
The history screen allows you to filter by character so you can review who's said what and such more easily. Hopefully that will help you navigate your unlocks.