what do these lyrics mean from the band papa roach?

I tear my heart open, I sew myself shut
My weakness is that I care too much
And my scars remind me that the past is real
I tear my heart open just to feel...

People are mean and cruel.  Be careful to tear your heart open to people

and only do it to

people you trust. I tore my heart my open to every one around,

 I can't believe it but that

I did that, but it happened.

I know what my life is about, I need to sew it shut.

But, do I sew it shut and never open it

up again, or do open it at the right moments.

or is it too late and people no what's in there

already...

out, J