I want my ex girlfriend back and I don't know what to do...?

My ex girlfriend and I dated for 2.5 years.

Early in February, she told me that she wanted a break. I didn't understand. So for the next few days, I kept bothering her, looking for answers and pouring out my feelings to her. She then broke up with me. Every few days, I would still contact her, still looking for answers and pouring out my feelings to her. I even begged her to give me another chance. I tried my best not to contact her after that, but for the next 2 months I would cave in every few days. I was still looking for answers and trying to convince her to rethink her decision. I can't believe she actually put up with me.

Not contacting her became easier. Finally she gave me an answer that I understood. I haven't poured out my feelings to her since, other than telling her I miss her once or twice. However, now, every 4 or 5 days we'll have a normal conversation. Sometimes, she'll even contact me first.

1.5 years into our relationship, she had the idea of promise rings. She told me to keep it "just in case". She also told me that I am not the problem, even though I have a hard time believing that.

She's moving back to California (we're in New Jersey now) after we graduate college in a few weeks, but I still want to be with her. Neither of us have a job lined up after college. I always told her I'd move to Cali with her if I had to. I know she's not against moving back here eventually.

I have no idea what to do. I care for her so much, and I just want her back.