Alrighty then,let's start saying where there is right and where is wrong. She over reacted when you said that "I lied to you 6 years ago".It's too much to not let it be water under the bridge and actually break up because of that.I smell underlying reasons. Big mistake on your part to ignore the calls. The fighting again and again is both of your faults,could have been avoided. The stalking is a good sign for you,means she gives a fuck,but in my book,that's a red flag,especially the other fake profiles.Could even means she is ill-intented.
Now, I would normally continue with the logical approach,but I know that when a person has been there for you,for hard times for a long time, it's hard to let go and none has the right to force your hand. Especially since you admire her.I am happy that in your eyes,you found such a person.Perhaps some people might disagree,but that is irrelevant.
Time heals all wounds.Eventually,if must be done for you to recover,you WILL get over her,unless of course eveything works out.She might stay as a friend,might not, who knows.What should be your first priority, is and will always be your psychological health.
Trust me,it's hard to find people this good again,but you will.Heck,you might even have met them and not have realised it yet. What's the worst part for you,is that she is everything to you,but it's obvious it doesn't go vice versa.
You will do what you feel/believe eventually,but please keep in mind,if not nothing of the above,this: In the end,what remains is you and your dignity.Let these be your priorities above all else and don't allow them to be trampled.
I hope you luck,and may the odds ever be in your favour.