Search Results: dont trust boyfriend

basically i asked her out and she rejected me saying she didn't see me in that way and added as we are flatmates she thought it would be awkward, this was a month ago! i took the rejection saying that's cool!

since than i acted distant/not phased by the rejection and she has started liking everything i post on Instagram even liking the same profile picture on both Instagram and Facebook.

she keeps intitating physical contact when she can
asks me loads of personal questions
started being overly nice to me
laughs at a lot of my jokes
talks about me when i'm not their
asks if i send nude selfies (bit random)
when she sees me asks what im up to this evening
always catch her looking at me when i turn
wanted to look in my room?
invites me to places she goes with her mates
she's casually dating a guy atm but never speak postivelly about him and deny's his her boyfriend and i overhead saying she dont trust him

it's not just me that has picked up on this as my flatmates have as well

I like a girl but she is extremely devious in my class.

- She never sits on one seat, she constantly changes her seat everyday.

- Then she flirts with me and if i dont make a move on her, she starts flirting with other guys. (I saw it myself)

- There are severe rumors in class, that she is married, or she is engaged or she has a boyfriend or she lives in a live-in-relationship, she has a pic of her and a guy as her wallpaper in phone, etc etc, every guy gives a different theory.

- Some guy used to drop her and pick her up before and after the class but now there is no one and she uses public transport to come and go.

- What should I do?