TW - Sexual Abuse

Hello everyone, it’s a first for me here on Reddit, even though I’m seeing a therapist now, I feel like this isn’t enough and I don’t have enough time to talk about this specific issue. So here I am to ask for help.
Without going in deep details and all the surrounding issues, I (22F) have been sexually abused by one of my three older brothers when I was 7-8 years old for several months. He is 4 years older than me, and at the time I really didn’t realized that what he was doing to me was really wrong. He used to blackmail me into doing things and not telling anything, but I really just thought it was something normal. And then all of a sudden it stopped. And we never ever talked about it since then. From this age until a couple of months ago, I still had those memories but never thought anything wrong about it, and my brother and I developed a really strong bond, like he really was my favorite brother and we share so many things. Just a ‘healthy’ strong brother-sister bond. Along the way, growing up, and especially when I left home at 17 for my studies, I started having anxiety, eating disorders, insomnias, depressive phases and this autumn a really hard depression.
But in January, I finally talked about this  for the very first time to my boyfriend. And it’s only at this moment that I realized what I just said. Looking at his face, realizing the words that just came out of my mouth. All of a sudden all the repressed feelings, emotions, memories, everything came back altogether and overwhelmed me (my therapist explained to me that I suffered from traumatic dissociation). The worst thing being that I had to stay 3 weeks in the same house as him, acknowledging everything. I clearly hit rock bottom. Crying every night, begging for help, having to hear him telling me « Why are you so rude all of a sudden? What have I done? » and not being able to tell him. Feeling anxious and in danger all the time. Having to hug him good bye when I left 600km away. I had already told my mother that I needed to see a therapist and she always forced to know why. And I didn’t want to tell her for a lot of reasons (that would be too long to explain here, but let’s just say that she has also been a reason for my depression and anxiety, even if she regrets what she’s done and told me). But when she helped me moving in, she forced again, and I told her some things, but not what my brother did. I didn’t want to break my family apart, that would be the last thing I want. But after she told me that she thought I was raped by my ex boyfriend, I gave in and told her. And she was in shock. She didn’t cry, maybe because she didn’t want me to see her cry, but I know that later that day she did. She also felt very guilty, asking questions like « Where was I when it was happening? Why couldn’t you tell me? Were you afraid of me? Could have I noticed it? », and telling hard truths like « All this time I thought your ex raped you when in fact it was your brother ». A few weeks later when I was calling her, she asked if I was sure it really happened. And the thing is, I know she wants to know what’s happening in my therapy sessions, what I’m thinking, when I’m at my lowest, but she really is not the person that will help me, on one hand I want her out of my business but on the other hand I know it’s legitimate for her to know a few things. So I don’t know what to do, and I don’t know what I should do to reassure her, and to let her know that, even if I’m struggling and that I sometimes go through hell, I’m not alone and I don’t want to hurt me anymore, and never really wanted to end me. So she doesn’t need to worry, just let me heal and process everything. (I tried telling her that but she’s not really receptive and still forces sometimes). Please help.
And thank you for reading everything, I just realized how much I wrote, wow sorry.