First, some background info please. How long were you dating before you said "I love you", and what was her inital reaction to that. Depending on the length of time, it's entirely possible that you said it too early.
However, just to give you the benefit of the doubt, I'm going to assume that you waited a decent amount of time to say that.
As for you questions, I'll do my best, since I have gone through some breakups.
1) It is always possible that you could get back together, but probability is an entirely different story. It all depends on whether she was being truthful when she said that she wasn't ready for anything that serious or if she just thought "uh oh, in too deep, better bail". Since complex percentages are complete and utter bullshit when it comes to relationships, I'm going to make this simple and say you have a 50-50 chance of getting back together (i.e. either it will happen or it won't). However, should you try to make this work and try to get back together and it becomes clear that the effort is futile, I would advise you not to expend all your energy on this one endevour. I know the old saying "they're plenty of fish in the sea" is played out and does little to comfort people, but it's true.
2) While it will be hard for both of you (the actual degree of difficulty will depend on how emotionally invested you were), the best way to do this is just go back to the things you did before you started dating. And if possible, try to avoid one on one meetings, as they can make for unnecessary/unwanted complications in the "going back to being friends" thing. When I broke up with my exgirlfriend (who I am still friends with), what I did was give myself breathing room from her for awhile. I didn't go out of my way to avoid her or deliberately ignore her or anything like that, but basically kept interaction to a minimum until I had gotten over it. How long that takes depends on the person, so there is no set time frame.
3) To determine if she was lying when she told you, we would need to know how she said it, what her facial expression and body language were and we would need to fully understand females in general (which will never happen, but mystery is good in life, so I'm not complaining). Unless you know everything that's going on in her life, and everything she is thinking, it's almost impossible to know for sure if she was honest or not. Sorry I can't be more help with this on, but that's the way I see it.
Wow, that was a long post. Good god, I think I'm turning into Aylaine XD
Oh, and OP, Aylaine and BonsaiK both give pretty good advice (much better than anything you will see in my post) so I suggest messaging them. BonsaiK used to have a relationship advice thread, but that has since been locked, so a PM would be the way to go. I've gotten more advice from Aylaine, so I suggest asking her first. Tell her that Hank sent ya.
