Well, because the story is through HIS point of view. But if we think a little : he doesn't ask anything. He's telling her he love to see her suffering, hé hâtes and despises her and NEVER did hé think that IN PRISON, when everybody is already bullying her, she could bé tortured.
Like come on boy. I understand that you didn't truly understand what prison is, but it can't bé a pleasant time.
She's traumatised and broken, with nobody by her side except a lunatic who act as if hé loves and hâtes her at the same minute.
She can't speak, she can't even think about speaking. Hé has to ask her, not just trying to ask her.
PS : i totally understand why he can't bring himself to ask, and i think it's a pretty good story until now for this point, buuut, as we see his point of view, i had to bring hers.

i like the concept and everything but nobody is communicating and i literally feel like i'm going crazy. i'm more mad at fl cuz she is not telling rihanel anything despite him at least trying to ask questions (like about the penitentiary and why she betrayed him) like there is no reason for her not to talk. i don't get it