How can i get over my break-up?

My boyfriend of seven months recently broke up with me because he doesn't want to be in a relationship right now, and I feel terrible.

I feel awful because I miss him so much and want him back, but then I also feel guilty because I feel like I was a terrible girlfriend.

He used to irritate me so much and I was miserable when I was with him all the time. Looking back on it now all I can think about what I could have done to be a better girlfriend. I want him back so badly, but he won't take me back. How do I get past this guilt?