Why does she already need space?

Don't keep calling if she is ignoring you, there is a reason for it. Honestly, it's probably not good-but you have tried to call, etc. She knows you are there waiting and if she doesn't have the courtesy to tell you anything-move on. Even when I am so pissed at my boyfriend that I tell him I never want to talk to him again-I break done and call or at least text him. If she can't even tell you why she needed space or return communication in some way, why would she be worth fighting for? My advice is to let her go!

She could still have feelings for her ex and now she is having feelings for you which scare her. 4 years is a long time to be with someone and to just move on so maybe she is trying to distance herself from you to figure out what she really wants in her life. I would say give her some more time and space because if you push it she might just cut you loose altogether. I am going through something similar, my ex and I broke up at the end of January and I met someone but I am keeping him at arms length because my heart still hurts for my ex. I have also learned ( from my ex who said he needed space) that if you push communication and not respect their wishes, they will rebel and drift further away.

You never know why, but if you push her about it, you will only push her away! trust me on this! the only thing you can do is respect her space. if she isn't returning your calls, stop calling. act indifferent. maybe date others, I said date, not sleep with. have fun and try to enjoy the company of others, this is really all you can do until she is ready to talk, she will let you know when that is! best of luck