Caught my dad cheating with his brother's wife.

I (18 F) live in a joint family. We have a two floored house , I life on the top floor and my uncle lives on the bottom one .

We are a close family not very close but yeah close enough. So one day I was sent downstairs to hand over my aunt somethings . Her room was locked from inside which was pretty normal, it was about 4-5 pm the time when her kids went for tutions .

So I was waiting for the door to open so that she could take the stuff but she was taking quite a long time for opening it which I found sus.

Then suddenly I saw my father trying to wear his t-shirt inside the room through a narrow opening in the door.

I was devastated, I instantly believed my eyes because I had a feeling that he was cheating from the past two years , I've also seen his chats with heart emoji with a person.

I've also asked him why he saved our aunt's no.( the one he cheated with ) by a guy's name (also 2 years ago ) . I also kept and eye on him at that time and he noticed it and confronted me about it . He covered it up and I was too confused and scared to do anything else . So coming back the door opened he was obviously hiding, I handed the stuff to her and ran off , they didn't knew that I know . It didn't had the strength in me to go through the confrontion at that point. I literally broke down, this shit changed my life forever, I hate my father and aunt and they're dead for me now . I asked two of my close friends about what should I do next and they told me to pretend like nothing happened till I went to college and get a job and then kick my dad out of our lives and make a good life for my mum that she deserves but never got.If you grew up in india so this is the most ideal response you can get . My friends told me not to tell my mum as she is already suffering the loss of her mother and is still in the grieving process. I totally agree with them on this . I decided not to do anything, until the next day I DID . So on to the next day, it was very hard my father definitely didn't knew about this whole situation. I ws trying to be fine until it was 4 their time to meet again. I couldn't hold myself , I couldn't let that MF be cheating on my mum like that so I went downstairs. I heard some gross notices and knew he was there . I banged on the door as loudly as I could and finally that bitch answered. I was having a panic attack, my heart was beating out of my chest , I said that" I know he is here and I know where he's hiding, you ruining my life " I did not had the strength to confront my father as well ( who is still hiding) . I was out of my breath and ran upstairs. 2 mins later my father came to me he said that he wanted to talk to me . I knew this would happen. So throughout "the talk " he was saying unbelievably narcissistic things like " how dare you insult you father like that , think about me for a second, I dare you talk to me like that , I will not be in your life now " followed by some other psychopathic stuff . That man didn't even apologized even ones . My heart broke for my mom who didn't deserve it at all . So it has been about 5 months to that incident , my studies are fucked up , I'm preparing for jee ( one of the Hardest exams in india) and ik I'm not gonna make it . For my father nothing's changed he still is narcissistic, shout at me and my mom , behaves like a psychopath and dominates everyone . I think he's still cheating I know he is . I can't tell my mom as she is already depressed about many things , we don't have anywhere else to go . Thankyou everyone for hearing my story I will kick this man out as soon as I stand on my own feet and I'm gonna give my mom the life the she deserves

Edit 1 - So since all of you are asking me to tell my uncle , mother and grandparents, I cannot. There's a lot at steak . If I tell everyone or anyone most likely my father wouldn't support my college expenses, and we don't have anyone else to support us financially. I also have a small brother and even if he sent me to college (most likely not) it would be a living hell for both my mother and brother. Maybe you all are right I should tell them but I am not ready for the consequences, I'm weak and I can't handle anymore shit at this point. I know many of you will be disappointed, I'm sorry but this is it for now.

Edit 2- I don't think she knows about this, but I definitely think she was suspicious at one point but she is a bit delusional, she never tried to ask him about it or just keep an eye on him sometimes to see where he's going . Also because she and my aunts are very close so she trusts her very much, if she knew she wouldn't be nice or normal to my aunt, like she is now .