<human>: Condense the text into a few key points

I met this girl about 2 or 3 weeks ago and from the start we agreed to keep things casual because I was going to school full time and working a job an hour away that left me with very little free time.

Anyhow this has happened a few times already. She asks me to come over and spend the night or come and hang out and I have to turn her down because I have other commitments, usually either studying or work early the next day.

Anyhow tonight I get a call from her asking if I could come over, I decline because I have a midterm this friday that i'm busy studying for and work the next morning at 6am. I turn down the offer because I can't risk being late for work and I have studying to do in the meantime anyways. She gets upset and says that she shouldn't have to work so hard to get me to come hang out.

Part of me feels like I'm being a shitty SO by constantly blowing her off but the other part of me says it's perfectly justifiable because it's not like I'm blowing her off for videogames or Netflix, but rather for pertinent thing's that I have to get done. Furthermore we aren't even technically a couple, I said I wanted to keep things casual for the exact reason that I was too busy for any kind of relationship at the moment.

I like this girl so understandably I feel a little guilt for blowing her off so many times in the past but then again I tell myself this is why I told her I wanted to keep things casual, because I knew I would end up not being there a good bit of the time.
Please help me guys, am I being a shitty SO or are my actions justifiable?
<bot>: Casual relationship. Can't hang out with her because I'm very busy at the moment. She's upset because I can't be there and I feel thats unjustified because I said from the get go I am very busy.