Of course this is just an opinion, and only knowing the bare minimum of facts but what it sounds like to me is that it was either a situation where you loved her more than you thought you did as others have said, or it could just be a situation of feeling rejection. No matter whether you were really in love with a person or not, I think it still hurts when they turn you down. I remember being in a relationship with someone who was head over heels in love with me and I was never certain of how I felt about her.. I had thought about breaking up with her many times, and then out of nowhere she broke up with me and I was just utterly amazed.
Anyways, as a side note.. I hate the silent treatment and don't really agree with it as a method to solve problems. It can turn a completely normal and sane person into looking "obsessive compulsive" or "crazy" and I can attest to that. One of my ex's used to give me the silent treatment every time we would have a fight. Her reasoning behind doing that (I actually asked her one time) was that she felt as though if she continued the conversation while we were both angry and hot-headed, one of us or both might say some things we regret and she'd rather talk with a cooler head and time to think about it.. And yeah in a way that made sense to me but when you have a heated argument with a person and next thing you know they completely avoid you it just fuels the fire. I said a lot of regretful things to her when she ignored me. I blew up her phone, her e-mail, text messages, etc... because it just drove me nuts not to get a response. Anyways, that's all. Sorry for the jumbled thoughts.
Be careful with your heart, because when someone seems too good to be true, they usually are.