AIO gf lying about her past?

So I’ve (21M) been with my gf (20F) almost two years and for the most part it’s been good.

unfortunately since the beginning she’s told some stories that seem very one sided or like she’s trying to vilify/hide someone or something but I liked her so I let it go.

Over the past two years I’ve noticed a few things such as her tendency to butt heads with coworkers and somehow it’s never her fault (weird right? lol) well because she’s never given me a reason not to trust her up till this point I again let it go thinking maybe she gets a little confrontational with rude coworkers in the professional setting.

Well today my perspective changed and I’ve been made to look at it all in a much different light. She hates chicken strips has since we got together and told me the reason is that before we’d met she had made a male friend, she didn’t have a license so he picked her up to come hang out at his house and somewhere along the way he pulls his dick out and says “put your mouth on it” to which she says “no wtf” and makes him take her home, he offers to buy her chicken strips to make up for it. Seems realistic enough

Now I also thought never eating chicken strips again because of that is a little ridiculous but I just said fair enough and let it be. Well today she’s hangry, I had to rush home for something so we didn’t have time to stop and since we were here I decided to just make something at home and asked my dear gf if she wanted chicken strips not even thinking about it.

This where I learned something my friends, it’s the juicy part. She looks at me says “no I don’t eat chicken strips don’t you remember the story?”

I go “oh right I’ve heard it a thousand times it’s silly hardy hardy har” just poking some fun. This girl looks me in my eyes, her boyfriend, and says “yeah you try swallowing cum then eating chicken strips and see if you still like them” I could see the moment she thought “yep not gonna be able to blame this one on being hangry”

So after this revelation my heart drops and I start literally shaking with anger, I kept it cool didn’t say anything kept a straight face, did my best to bury my genuine reaction like a man.

But according to her it was in my eyes and I was of course visibly shaking.

I say “that is not what you told me” she goes “you look like you wanna kill me” I say no I don’t wanna kill you, don’t change the subject, I want you to tell me the truth, he pulled his dick out, said put your mouth on it. then what happened” and she goes “well he was my ride home so” queue dumb little hand gesture. “And I ended up swallowing cum”

I start saying “I’m ok, you’re ok” over and over, under my breath trying to calm both of us down because if I have the conversation in my current state I’m gonna blow a gasket and say things that cannot be taken back, so I say “get in the truck” I silently drive to get her some food, come home and don’t say a word for the next hour.

And I can’t even be blamed for prying at information I knew I didn’t want to hear because that was obviously very much NOT the version of the story she originally told me

So here’s where I’m at. The story was not the true version of events to begin with and I believed it for two years, come to think of it actually I mentioned it being fishy once and she doubled down on what she said happened so that’s a double whammy.

Second of all we were very open in the beginning about how many people we’d done explicit activities with. I gave her my genuine honest number, she as I have now learned did not and honestly given the similar nature of several other stories she’s told (that for sake of not making this any longer I won’t get into) I don’t know if that’s the end of it.

for all I know it could be wayyy more and the weird plot holes and parts she “doesn’t remember” seem to be filling themselves in with what any sane person including myself would have originally thought but I chose to believe her because I’m a doofus.

So right now she’s at home and clearly knows all is not quite yet forgiven and I’m seriously wondering if everything she’s told me about her past is either blatantly untrue or if there’s major plot points being intentionally left out and I’m considering walking away.

Now I want to clarify a few things

1. I know everyone has a past, I certainly do. But I also feel like if you’re looking at dating someone and you’re talking about your pasts you should be perfectly honest with them, which I was with her. Had she just told the truth from the beginning I wouldn’t even give a shit at this point.

2. she knows she fucked up it was in her eyes the second she said it, anyone that’s had a gf knows when they mess up they’ll often try spinning it back you so you really gotta pick your battles lol. This time? She didn’t even try it. Realized she fucked up both in what she said and the fact that she was caught in a lie and immediately accepted it.

However that doesn’t just make me believe I can trust her again, if anything it makes me think she’s gonna try a little harder not to get complacent and spill anymore little secrets

3. I’m 99.9999% sure it was not SA. She’s had those experiences and has told me about them, one of them was pretty graphic so if this was that I don’t see her sparing me the details especially for two whole years

Anyway that’s the end of this super long spiel. Am I overreacting ?

TLDR: caught my gf in a lie that I consider pretty major and I’m not sure if I’m gonna be able to trust her going forward.