I feel like my coworker crossed a social line and I am confused about it?

So I get along with one of my coworkers (F30/31). We have been working for the same department for 4 months and knew eachother from "down the hall" at the office before. We both like the same TV show contest and since yesterday was the finale, she kind of invited herself earlier this week to come over and watch the finale at my house.

Nothing was weird. I prepped some snacks and such and she gave me a handmade Christmas card. We watched the show a bit till the first commercial block. I have a TV which you can pause and fastforward live TV shows and we were talking about so much that I paused th TV at the end of the commercial block.

Here is when it gets a bit weird. I am studying psychology next to my job so that might add some context? My coworker had had a boyfriend for 8 years now.

My coworker starts to talk about how another coworker can be a bit "off" sometimes. I agree with her and then she says that she has autism, which did not surprise me. I responded with something generic like "everybody has something". Next she asks me if I wanted to try to guess/diagnose which traumatic event she had in her life. I felt uncomfortable doing this, so asked her if we could continue watching the contest. She then starts to talk about how her childhood was traumatic (sick father, disabled brother, lots of bullying) and how she lost her virginity; she was raped at 17 by the boyfriend of her best friend. She starts to talk about it in details and while i try to have her not go into detail ("you dont have to relive that painfull memory") she starts to describe how she layed there in front of the bed etc. She concludes her story with that she is over it. I am flabergasted and say something generic about her being brave.

We finally go back to watching the show, a full hour later, and she starts to talk about her hair. She asked me if I liked it, I said sure. She then wanted me to touch her hair. I refused. 10 minutes later she asks if she can take her shoes off. I say ofcourse.
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She then takes off both her shoes and her socks, saying that her feet are really cold. I roll my eyes (why take off your socks then) and asks if i have to adjust the heater. She then puts her bare foot in front of my face and asks me to feel how cold it is. I say that I hate feet but for a full 5 minutes she keeps trying to have me touch her feet.

After this she watches the contest with me normally, eating the snacks and reacting to TV.

After this social interaction I feel very confused.
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I have not made new friends in a few years and my very social boyfriend (who lives with me but wasn't there when my coworker was) says that this is how people socialize.

Any advice with how to deal with this? I am really turned off by now further socializing with her, but we work together so I can not shut her out of my life. Changing departments is also not an option. Also, why would she open up to me like that and then act so set on me wanting to touch her?
I feel like my coworker crossed a social line and I am confused about it?
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