This is so sad Yakz; heart breaking but at least as you said, a lesson learned is worth all the pain endured..trust me :)

I love the poem, and the way you worded it, sounds like you expressed everything you felt..

however

crushed into pieces
lost in disbelief
you a puppet master
and I,perhaps too naive
^^

this was my favorite part..
i love this stanza and the words choice u
chose for it; as well as for the way you wrote them down..

suggestions; you need to repuncuate the stanzas.
and

left me alone
wanting to die
played me too well
I'll never know why
^^^
the last line sounds really forced and was weak;
it affects the poem..and you are better without this one ? as you want :)

PS: big girls, do cry when its needed ;) do it even if you had no shoulder to cry on

I agree with the above comments.

crushed into pieces
lost in disbelief
you[,] a puppet master
and I,[ ]perhaps too naive

I think it was ended abruptly, though I really liked the beat of this piece.

Hey, Ive written something out of this title as well.

Here, have a look:)

http://www.poems-and-quotes.com/sad/poems.php?id=1001586