Feelings or thoughts for my female cousin which I can't understand the reason for them happening & I want to get rid of it. What should I do?

Background: I( M, India, Early 20s), grew up in boys school with zero proper female interaction. This school I studied in an all boys catholic convent school which had a toxic environment filled with mostly toxic & abusive & uncooperative teachers and bullies; where only the grades/classes 1 year below us had girls as the school had introduced co-ed in 16 years ago while I had taken admission the year prior to that. Also in 2014 when I was like 11 years old, one of the subject teachers told & schooled one of my classmates, that he should not give rose & chocolate to a girl as he had given them to a girl 2 years younger & junior to us. I never interacted & was shy to talk to with any girl from my school. I was always a lonely kid or always felt lonely & boredom was always present in my life, no pet, no siblings, no proper friend groups nothing. People would always use me & I would not be able to pick up social cues etc to figure out who's lying & who's being genuine. I also wanted to change my school like 13 years ago cuz the kids there would never let me play anything.

So, Let's call this cousin Molly. We have known each other since we were kids but never grew up closely with each other like school friends or siblings in school or like siblings & cousins do together in the same joint family house or neighbourhood. When I was 6 to 7 year old child I found her face card & eyes to be pretty before I came to know she was my cousin. I still found or acknowledged her facecard to be cute or pretty when I was a kid i.e. 9 to 12 years old but I never had any ill intentions back then as a kid. I would only meet her in my or her birthday parties or occasions which stopped 8 years ago. She has also come to my house to play video games only twice or thrice 14 or 13 to 12 years ago, I think it was me who requested my mom & her mom to let her visit because I was bored & also I think because I liked playing or spending time with her for some reason; was I fond of her?. We also used to watch the same cartoon( I cannot say that because If she sees this she'll know & I don't think I want her to see this rn).

So throughout the years of my early childhood to pre-teen I eliminated & ignored & controlled those feelings whenever I would see her in family functions or birthdays or occasions; I also didn't interact with her as much in those events/functions/birthdays as I would mostly keep to myself sitting quietly but would talk to people when needed or would be playing video games with my friends. So she was just there. 9 - 10 years ago I also attended a dance program she performed in & we also met in her female friend's birthday. Lately we haven't seen each other that much i.e. there's been a few years of gaps in between. I met her twice 8 years ago in family occasions & once 6 or 7 years ago. The last time I saw her was around 4 years ago in a family function. She also turned out to be the mature / emotionally mature one way earlier than me around 11 years ago.

Note: I discovered the thing we boys/men do accidentally when I was a kid around 14 years ago when I came across a suggestive compilation video of Spider-Girl from the comics but I obviously never thought about her while doing that during those first few years.

Main Context: My early to mid teen years( 13 to 16) were very dark & almost bleak (so were my late teens but not as much). I didn’t want to study in the school at all & lost interest in studies. I had no idea about intimacy or reproduction process at all & was gullible. Then I had been exposed to that intimate scene from Deadpool movie (2016), the same year, forcefully by a schoolmate( who later turned out to be a bully) in the school computer lab during a computer practical class even though I did not want to watch it nor sit with him as I was scared of getting scolding from the teacher; and from that day onwards I started getting addicted to sexual content: starting with & watching, movie intimate scenes from movies like Friday the 13th( 2009) & watching YouTube videos about lewd drawings of Dragon Ball characters with the thumbnails displaying almost uncensored version of the drawing. Later, 9 to 10 years ago, when my dad broke my Nokia Lumia 520 & I switched to using my mom's phone as my phone most of the time, this then led to watching & consuming 🌽 videos & h_ntai( most of the time/as well as inc_st h_ntai ) & consuming/watching ecchi & harem genre anime such as Motto To Love Ru( I think I did watch the prequel To Love Ru) & comedy, romance, sports anime such as Grand Blue Dreaming which also had some content of incestuous moments/ " jokes ". I then led to me discovering Discord in 2018 but I hadn't been exposed to adult games on the internet yet. If only my parents listened to me back in 5th or 6th grade over 12 years ago, I'm not even sure which grade it was now, that I wanted to change my school because of the physical & mental abuse & frequent unsupportive & uncooperative behaviour from teachers & students/peers since class 1( no form of sexual abuse yet back then), I would never have fallen into such bad influence; most of the kids there from my batch, they weren't naive & innocent & already knew about 🌽 since grade 5 or 6 which I heard were shown to them by the seniors from, I guess, 6 or 7 depending on what grade we were in that time. As I said before I had already discovered " male alone time thing " accidentally when I was a kid but till like 7th grade I would do it very rarely to rarely as I believed it was a sin back then, which I now realise wasn't a sin but was indeed a bad exposure for me at such a young age.

So recently this year or so, When I opened up & reached out to her about my abuse & trauma, she had no idea about any of it & was the only one to understand me, validate what I said, help me, give me closure & empathy which I didn't expect and she has given me good advice & has also said I can talk to her whenever I need help; I never knew or maybe I didn’t realise yet that she cared that much for me. We have talked more in text messages recently than all these past years like real friends with funny stickers etc. This is why I am so ashamed at myself & I can never forgive myself for what I had done; I have never had a fight with her nor vice-versa and realisation about the fact that I thought about someone who loved me unconditionally in this way makes me angry & guilty & repulsed by myself.

I knew I shouldn't have done it because back then, If I vividly remember, my conscience or a part of me warned me not to do it but I couldn't control myself or rather didn't. I don't know why I couldn't control myself. Was it because she was the only female I would interact with who was close to my age & generation? Or was it because I found her pretty? Or am I making excuses? I still sometimes feel I cannot live like this as what I have done is unforgivable. My mind or part of it wants to tell her or is imagining telling her the truth with her forgiving & understanding me but is that really what's gonna happen? Maybe not, because I think she's gonna be disgusted & repulsed & would never talk to me again & would feel unsafe with me & I don't want it to be that nor do I want to lose contact with her, why the hell would she forgive me If I tell her this? ; Why the hell did I have to watch H_ntai & do that man? & why the hell was I so immature?

Why the hell did I forget my true self who had no ill intentions about her? Why the hell am I realising these things now & not before?, including the fact that she would've helped me & would've supported me and I would've been a way better person If I had told her or even my other cousins & aunts & uncles or even my mom everything about my bullied, shunned, alienated school life early on when I was still a kid.

I almost felt like doing self harm but I have decided not to be a loser & make most out of my life. I have also thought about going completely no contact with her after sometime or when she's engaged in a few years because I can't talk to her with this guilt acting like everything is normal but I can't bring myself to do it.

Idk guys, what should I do? I have to know or there must be a / the solution & explanation to all this. Even though I am trying to do my best to redeem myself, why am I still feeling these things? I am sorry If I am being overly emotional or dramatic but this is the only way I am able to fully express & explain what's happening.