Did I make a mistake?

My girlfriend and I have been dating for about 8 months now. We have gotten to the point of being very serious as well as being very intimate. The problem is...it is summer vacation and we both live in different locations. We started dated at college. She lives only 3 hours away from me. She doesn't have many friends back home but guys...most of which she has had a crush on..and one of which she has dated before. A few weeks ago...she attempted to meet her ex boyfriend because she never got closure from their breakup...only to tell me she still has feelings for him...and then a few days later she went to the movies with two of her guy friends...one of which she was crushing on prior to our relationship. Now here is the dumb part...one day out of the blue...she doesn't reply to my text messages...nor my phone calls...and for an entire week she does this...so I have no idea if shes hurt, or okay, or cheating, or her phone was busted. So she finally gets back to me..and her reasoning was..she just didn't feel like talking to anyone. I asked then why didn't she just say she wanted space because I was okay with that. She said she just couldn't.and that was it..we conversed about it for a while because I was upset she just shut me off like I was her phone...yet she claims to love me. By the end of the conversation she gave me the Ultimatum :"If you want to date me, you have to get used to me doing this cause thats just who I am"...I can't get used to being ignored....and shut off...not without being told..I can't handle not knowing if shes fine or not...yes I get people need space and I would have been okay if she just told me...but she said that her telling me she wanted space...makes her not be in controll...and that me asking that of her is me telling her who she can and can't talk to when she wants to talk to them. I broke up with her because of it, but it kills me to be away from her. At the same time...I can't just accept being shut out, and she says there is just no way she can promise she cld tell me before hand...if she goes MIA...we tried to work it out but only went in circles...but I hate that I hurt her...and hate that it came to that. Did I make a mistake? was I wrong to do that?