So, I have been working my ass off since January with my post-graduate degree. Usually I'm working from 7am to late night with no weekends or holidays as we always have a project that needs to be done or a test/exam.  This week is the final week of the term and I'm also writing a test on the last day. We have a week off after this.  The problem is that  I dont get to see my gf much as she live a bit far and attends a different university. I only see her on weekends and because I've been so busy I only have been able to see her maybe 1 or 2 days of the week, the last couple of weeks.  However, she has gone out without me a few times with her friends because I'm literally too busy.  I'm always happy if she goes out because I know she struggles with friends and dont want her not going just because I have work.    
She messaged me that she does not want to go out on the last day because she has doesn't feel like going out and if she comes she going to stay back when we go out in town.  Which is fine, a bit bleak because I've been really keen to go out due to being trapped in my room working.  I asked her if it would be fine if I go out with my friends for a couple of hours and come back later that night.  She said it's fine but will be sad if I leave her there.   Because she knows I want to go out she says she maybe won't even come because she's going to be a wet blanket. So now I feel like an asshole for going out with me friends and not having my gf with and if she comes she is staying at my place sad till I come back.   


Also: she says I always chill to much with my friends when we go out and that we do not chill enough together.  Which is partly true I feel, but it's not my intention to neglect her.  I switch conversation often between people and just enjoy not being stuck in my room and socializing.