How to reply??What to do?? (urgent!)?

[David]

My best friend is afraid of relationships .. She had only one and it went so bad ..
She loved the guy so much but he cheated on her ..

I told her that I like her and she told me that she is not over ex and
she doesn't like me that way + our friendship is great and she doesn't wanna ruin it

I told her fine, just forget everything I said. and be just friends

Then I noticed a change in her way of treating me..
She became kind of cold ..

I asked her about it ..

She was like .. We can't be friends anymore, it is weird ..
After what happened we can't be as close as we were ..

I tried to convince her that everything is fine and nothing happened ..
I was like, I just told you that I like you!! You don't like me back? Fine, let's move on!!

At the end of the conversation I told her ..
You don't wanna be friends? OK, I can't do anything about it .. bye, I wish the best in your life..
and I deleted her from my bbm , facebook , twitter ... etc


_____________________


This was one week ago ..

Now she just sent me Happy birth Day message!

How should I reply???
Should be like " Thaaank you .. You're the best!"
or more like " Thank you!"

I dunno ..

+ what should I do next? Should ask to enter msn or something to chat?
I dunno pleease help!! I'm confused .. Why did she even sent the hbd massage!