Why did she invite me to her 21st?

[cutie7]

I had a fight with a guy for putting me on his back list after he rejected me... I deleted him off my Facebook...then the next day his friend adds me and said she added me accidently.... saw her friend list and he was there.... so asked her if she knows him and she deleted him first then full denied ..
Anyway we started chatting.... she seems nice... and exchanged long messages
then stopped messaging...
now after 6 months she sends me a message asking how I am... and then after few messages she invites me to her 21 st birthday party

ok the thing is.... one of my other friends know her personally but she is not invited.... whereas she doesn't know me but wants me to come ..
anyway I will be going with a friend ... just out of curiosity ... what could be the possible reason for her inviting me?

[Mister Awesomest]

Maybe she REALLY liked chatting with you? It is odd, but the possibility exists, and that seems like that's it. She may have not invited the other friend because they don't get along or their not close. I have friends that I love to death, but I would never invite them to my b-day party because we don't get along.