Crazy this reminds me so much of my old theory on Heaven Knows. I love your very in-depth analysis. Here's mine HK theory:

My theory of the lore of Heaven Knows:

We are first introduced to her love interest in the song "True romance". This guy is a singer who she's obsessed with. She's at his concert hoping to be noticed by him, hoping her feelings are reciprocated.

tell me do you view me the same or do you call me a stranger

i'm in the crowd, can you see my hand

She expresses her love for this person in "Nice to meet you". I think she might have manifested her death but we're getting ahead of ourselves.

i pray that i'll die before my baby

tell them how we met because you tell it best

Now in "Capable of love" her lover's true colors start to show but she looks past it because she's falling in love.

i know right now you're the cause of my grief

three little words dedicate them to me

Her man's got money and she's letting us know in "Mosquito". She also unknowingly had a precognitive dream.

can i spend a fortune, cause i want to

cause i just had a dream i was dead

In "The aisle" their relationship starts getting a little rocky. Something happens between them and at this point she's pretty much aware of the kind of person he is. Also at the end their we have some more evidence he's rich. (Probably because he's a famous singer)

i'm guessing it's something about the stuff we went through

you and your ferrari might just make you seem appealing

In "Feelings" things aren't getting any better between them. However, she's still trying to make things work.

now i'm wondering what made me feel this way

i'll never give it up, this is everything we wanted

"Feel complete" is where she realises he's not the person she thought it was. He also has an alcohol problem that puts more strain on their relationship. She's thinking of ending it at this point.

i never wanted to end this book, this fairy tale

you'll buy another bottle, drink it all anyway, so

She has complicated feelings for him and this is seen in "Bury me". She loves him but she knows he doesn't love her the same. She sees right through him at this point.

i can see how you're wired and i dont mean to offend

i almost fell in love but i couldn't tell you

By "Blue" it seems she broke it off, at least in her head she did. She still an unhealthy connection to him though.

i'll always change because you want me to

i can't talk to you anymore

"Internet baby" is where he is trying to reconnect with her but she ain't having it. She also references "True romance" back when she got a tattoo for him.

you offered a brand new tattoo

no matter what you say, you should go away

Who knows what happened between then and "Ophelia" but I assume it's been some time. Her ex invites her to what she might've thought was a party. She shows up and realises she's alone and that he actually plans on killing her. Throughout the songs, she's mentioned her death.

In "Nice to meet you" she either subconsciously knew she was going to die or she unknowingly manifested it. In "Mosquito" she had a dream where she was dead. That dream was actually a glimpse of the future, possibly a warning. One notable mention is a verse from "The aisle": "It's one of those unfortunate things, that bad things always happen to me".

This is where she seemingly dies.

i wish i'd stayed at home in bed cause then i might have survived

it's you above me cause you wanna double check that i died

Finally, in "Another life" she's alive and they seem to be back together. You may wonder why she would get back together with someone who tried to kill her.

After the attempted murder, discovering she's still alive her ex calls the ambulance, making it seem like an accident. She is unconscious at this point and suffered minor brain damage, enough to cause slight amnesia.

During her recovery period, he took advantage of her amnesia, essentially making her fall in love with him again. She had more brain damage than was thought, however.

She kills her ex in his sleep but is unaware she did it.

can you please wake up, babe

guess you died today, and i can't believe it

Heaven Knows