Feeling hopeless :( someone cheer me up?

So I thought I had a hunch a friend of mine MIGHT possibly like me. Either the signs were VERY subtle or I was just flat out wrong and she's just being friendly. But whenever class would end she use to wait for me and only me. Not any of our mutual friends. It's been a habit that I keep her company on her walk to her apartment. So every time class ends it's sort of awkward because it seems like we're both stalling while we're packing our bags without making it obvious that we're waiting to walk each other out. Like we won't directly come up to each other and ask to walk each other. it's sort of like happens. and if on the days where we didn't walk each other out or say goodbye I sort of got the vibe that she was slightly offended by it. one night she asked if i was going out that night and then asked if i wanted to go out saturday night. so we went out and I was not expecting her to show up to the bar alone. She worked that night 'til 11 at night so I thought she'd change her mind but instead she decided to go and texted me "just got home! getting pretty and i'll be right out!" she asked if i wanted to stay over her place that night so i ended up sleeping over. I didn't go to class on my last day and she texted me "Miss you!!!" and two days after school ended she texted me again "Hey! Miss you already ((((" I could be totally wrong about her even liking me that way. But she has indirectly stated that she was bi-curious one time when we went to starbucks together and the employer asked us if our order was "together" and she joked "oh yea we're together alright" and she told me she made out with two of her best friends before.

i know the signs are ever so subtle but that's because she has a boyfriend. to be honest i'm not even sure if she's really happy with this guy because they fight over pointless things and there's just not enough passion coming from him. They recently got into an argument and she ended up deleting him off facebook, twitter, and instagram. so i thought she might possibly break up. but 2 days later she adds him back. so yeah my hopes are shot pretty much. and now i don't know what to do because we have class together and I kinda want to avoid her. I'm just so upset that she's really trying to work things out with this guy. and that fact that I got my hopes up that she might actually like me. I doubt she even knows that I even like her. :tears: why do i fall for straight girls?