Read the following song lyrics and answer the question.

Jar of Hearts
(By Christina Perri)

[Verse 1]
I know I can't take one more step towards you
'Cause all that's waiting is regret
Don't you know I'm not your ghost anymore
You lost the love I loved the most

[Pre-Chorus]
I've learned to live, half alive
And now you want me one more time

[Chorus]
Who do you think you are?
Runnin' 'round leaving scars
Collecting your jar of hearts
And tearing love apart
You're gonna catch a cold
From the ice inside your soul
So don't come back for me
Who do you think you are?

[Verse 2]
I hear you're asking all around
If I am anywhere to be found
But I have grown too strong
To ever fall back in your arms

[Pre-Chorus]
I've learned to live, half alive
And now you want me one more time

[Chorus]
Who do you think you are?
Runnin' 'round leaving scars
Collecting your jar of hearts
And tearing love apart
You're gonna catch a cold
From the ice inside your soul
So don't come back for me
Who do you think you are?

(Adopted from: https://genius.com/Christina-perri-jar-of-heartslyrics (April 4, 2019))

How does the singer feel as expressed in Stanza 3?