I broke up my girlfriend who I used to go out

I broke up my girlfriend who I used to go out with almost a year, not because I don't love her anymore but because I can't tolerate her taking up all my free time since we had started dating each other, at which I would like to have some space for myself. And a month ago she told me that she's falling for a guy, I'm starting to regret that I didn't try enough to make her understand of my situation. But it's a little too late....