Cant blame her for not speaking up but going through it before and then expecting things to be a different is a bit naive, but she was young, and I know it can be a bit hard to deny in front of everyone in the awkward moment. But damn didnt even let her speak, she was only silent for a little while wasnt she? Disappointed in her friend, but those backup dancers were really annoying and unnecessary. If they werent there the situation could be cleared up.
And I can understand her not wanting to see her friend to clear it up because shes probably been through that situation before and has lost trust in everyone since she probably thinks the male lead probably gave it to her despite promising he would give it back. Probably believes she wouldnt believe her and doesnt have the energy for it, plus she might be a little angry and sad that she didnt want to hear it before and called her a liar.
Sad that the male lead means well and likes her but the girl earlier who liked him probably stole that shit and gave it to female leads friend, and the female lead never even explained it to male lead so the male lead cant explain the situation to female leads friend. But hes really stupid for keeping it this long and not giving it back or trashing it, I know he meant well but he could have been upfront about how he felt instead of doing that playful blackmail shit he did. But thats the authors choice so cant really fault him, but it builds up the drama of the situation so cant really blame the author either