Peter, oh her sweet boy. I’m setting this in delinquent because it’s the most emotional background we’ve got and it’s gonna be a RIDE !!
When Verity entered the skybox she was full of loathing, for herself, for the man that had gotten her put there, and for everyone. She was not confined with kids that hated her because of things she had. It made making friends hard and she drifted to the outcasts that had formed a little group, primarily Fox, Maeve, Peter and Murphy. Not all of them were friends with one another but she found comfort in being with people that were also overlooked or outright disliked as with Murphy.
Enter Peter, someone that saw the darkness and embraced it. Their friendship was grown on his acceptance of her flaws, and the way he didn’t think they made her. She grew basking under Peters gaze into someone that was almost herself. It didn’t stop her from doing what she wanted to survive, and when they became romantic it was actually because Verity believed she needed to thank Peter for his kindness. Her very firmly put a stop to that, and soon after that she was turning to him for needs that she’d never considered before like kindness and affection without a cost. This changed Verity, she stopped sleeping with the guards even though it meant that she no longer was gettin the extra rations, and it meant she couldn’t have Peter beside her at night.
She fell in love with Peter, although she would scoff at the notion. Verity had only ever experienced love from her mother and it was not at all like the storybooks and so she doesn’t really believe in the notion. She’d seen men say they loved her mother and yet they’d never stuck around, and so as a whole she’s disdainful of that. They were considered a couple, a silly title that thrilled her truthfully, by those around them. With that came tension in the form of Veritys need for attention and no one else having it. Peter was always devoted to his best friend and Verity kind of hates it, she knows at her core she will never be number one for Peter and because of that it makes her resent his connection to other people. She wants to be number one, and believes she deserves it, and so there’s this quiet resentment even as she tries to make friends with people for Peters sake.
She knows that Peter thinks she’s a better person than she is, and so she tries to be for his sake. When she’s taken by the grounders in season 1 she believes Peter will find her, it’s a belief she holds onto because of how he fought so hard for his best friend —- he got confined for her and he said he loved her, so why wouldn’t he come? But he doesn’t. Verity never gives that belief up until she returns and makes her way back to the drop ship and finds it empty and abandoned with scorched ground everywhere. She at first believes Peter didn’t come because he died and she grieves for him at the graves of people she doesn’t know ( but would later come to find out is one of her friends ). When she finally makes her way to the ark she’s surprised to see her friends alive but hollow shells of themselves just like she is.
What surprises and breaks her heart and her belief in love ( what little of it Peter had managed to convince her of ) is his relationship with another person. Peter had forgotten her, moved on, and left her behind like a memory. She’s angry, and a part of her hates him with all of her being, hates him in a way that she’s never hated him before. Peter had made her believe in love and then shown her exactly how much bullshit it always was. She doesn’t move on, oh no, Verity makes it her mission to torment Peter and hurt him in any way she can. Just as much as she hates Peter she loves him, and that more than anything hurts her, so she throws sleeping with people in his face and uses her body against him. She thoroughly believes that Peter no longer has an emotional connection to her and so she uses what she’s always used; it’s her only way to feel sane.
When they’re trapped in the bunker verity grieves for Peter, but also is happy that he is losing himself, but this all provides an opportunity for her. Peter needs someone and Verity is very good at being that person someone needs. She lets him seek out the connection and she listens to him when he’s upset, half because she cares ( and she does deeply ) and half because she wants to be the one to walk away and not look back.