Not my Ultraviolence interpretations being paid dust
The song:
it's a metaphor for a turbulent, dangerous, passionate, strong, volatile, intense relationship.
"he hurt me, but it felt like true love" and "he hit me, and it felt like a kiss."
she's compares the love she feels for him that is strong enough for emotional feelings (true love, a kiss) to feel like physical ones (hurt me, hit me).
this idea of good and bad continues to play out in the hook--dangerous/illegal sirens (the good/mermaid definition, or the bad/police car definition?) vs. beautiful violins are compared, like the relationship (the good and the bad of the relationship).
adam and eve, too. the idea of good vs. bad and the strength of a volatile relationship is constantly described in the lyrics
The album:
Cola, BB, WC, And SOC are all about Barrie. I'm sure there are more songs about him too on Ultra.
Also, I don't think Ultraviolence is an old song--I think it's relatively newer (definitely post-BTD), so she has to have a reason for putting it on the album. Not only that, but making it the title track! I think it's about being haunted and surrounded by the former love of her life (Jimmy, who is on tour with her). How that must feel? It must be strange seeing those old strong passionate emotions going to waste, and so as to respect the former relationship, she doesn't want to just let them did. But at the same time, she is in a stable relationship with Barrie. How must this contradiction of emotions between two people feel? Ultraviolent.
It's ultraviolent to be touring around with the person she used to love, especially while she's in another relationship.
It's Ultraviolent to love someone with depression (Barrie).
It's Ultraviolent to be misunderstood, mistaken, and lied about (in terms of her career launching off from a bad SNL performance and a preconceived notion of who she is that most people mistakenly have for her).
It's Ultraviolent wanting to live a wild, crazy and free lifestyle while being in the public eye (aka sacrificing some of who she is in offer to fulfill others' expectations).
It's Ultraviolent to fear failure after putting so much work and effort into something--fearing that it won't be appreciated like she wants it to be.
I think that all together, THAT is what Ultraviolence is.