I'm upset that my girlfriend ignored me all day
How did your girlfriend ignore you all day?
I can't reach her by phone or text. She didn't want to hang out with me.
You are not a child. Wanting your gf to be there on demand is clingy and dependent. Live your own life and stop leaning on your gf.
Who said I wanted to her to be there on demand?
I am sorry that I thought you want her there on demand but still you should be careful about coming on too strong and clingy. It might make her disinterest to know that you want her there all the time.