What Happened?

I really like this poem, however I will suggest a few changes. First off, you have barely used any punctuation, only full-stops. You should include more punctuation, commas, full stops, question marks etc. For example..
'What Happened?
What happened ' should be changed to:
'What Happened?
What happened?' as it is a question.
Also, without commas when being read is very breathless.
I like the way you rhymed in the poem, as well as the actual included feelings, as it comes across as a poem that is emotional and regarding special someone who you were once close with. It is clear that this is happening to you and you would like to know why. Therefore, whoever it is that you intended to make this poem for, should be touched when read

Hope this helps

Hi. I hope everything's getting better. I just tweaked the formatting a little. It's the message and feeling that counts and you portrayed the feeling well.

What happened?
I thought you were my friend.
Now you just walk pass me
not knowing who I am.
You found someone new.
She replaces me a little everyday,
but you don't know
that you have hurt me in every single way.
You NEVER say hi
You NEVER say goodbye
When I look at you,
I have sadness in my eyes.
I know I have lost you,
but you haven't realized
that I am gone in spirit and in mind.

I've been sitting in the darkness
for last few days.
I think my life has just gone insane.
As I sit wondering what to do,
I just realized I just said
goodbye to you.

Wow. This was really good. I loved this, it came from somewhere deep, and I can totally relate to losing friends....aside from a few little capitilizations this was awesome. I love it, awesome job.

~Forest