Had this exact same situation happen to me. We went out for about a year, lost virginity to each other, etc. She stopped hanging out with all of her friends and wanted to hangout every single day. She was incredibly dependent on me and I hated it. I'm an independent person and I wanted to spend time with family and friends as well. I ended it when I couldn't take it anymore. We stayed broken up for about a month and a half before we decided to try again. I missed her too much.

Things were golden for a few months after we got back together, but after that, the same problems started occurring. We're still dating, and not much has changed. I'm just as unhappy as I was before, and she's just as dependent on me. She doesn't get that I need people other than her in my life as well. If we aren't hanging out she misses me. She gets upset when I want to spend the night hanging out with the boys.

We also fight much more frequently now it always come back to the fact that I want some space, always. I'm not trying to dissuade you to not take her back, it's just that her being dependent is who she is. Her wanting to be with you constantly will not go away. Eventually your problems that you had before will come back once you guys have settled back into the routine of things. Don't lose sight of what caused the breakup just because you feel lonely.

Sorry if this is pessimistic. Just trying to give you some perspective.