As you may noticed, Halsey sings "I" pronouns so intense.
For example, in Him and I, she sings:
In the end, it's him and I.
In another song, Sorry she sings:
I've missed your calls for months it seems
Don't realise how mean I can be
'Cause I can sometimes treat the people that I love like jewelry
'Cause I can change my mind each day
I didn't mean to try you on
But I still know your birthday and your mother's favorite song
P.S. I bolded the "I" to show both the word of interest and its intensity.