It's EmiLY

Sometimes, I wish you would leave him alone.

You had your chance but you blew it, and now his mine.

I’m gonna treat him better than you did,

his gonna finally get the love that he deserves.

So just fuck off and let us be happy,

So stop ruining it for us cos’ I ain’t giving up on him like you did.

I ain’t gonna break his heart and leave him hanging ever again.