Violet goes for herself, not for any of Finch’s family members. She knows what she’ll find—and she knows it’ll be her fault. She made Finch leave his closet by telling her parents he was in trouble. Violet calls her parents and tells them she’ll be back in a while, and then she drives faster than normal. She thinks “there was nothing to make him last.”
Violet is purposefully cagey here about knowing “what she’ll find.” She seems to imply that she expects to find Finch’s dead body—but she’s unwilling to say it in so many words. By not voicing that fear explicitly, she maintains some control over the situation.
Violet sees Little Bastard parked on the side of the road before she sees anything else. She pulls in behind the van, something inside of her screaming at her to leave. If she leaves, Finch will still be alive. But Violet gets out, walks up the embankment, and then walks down to the Blue Hole. It’s peaceful and quiet. Violet notices Finch’s clothes folded neatly on the bank. She finds his phone in a boot, and their wandering map in his jacket pocket. Violet takes the map and then starts to say, “Marco.” No one answers.
It's significant that Violet describes the Blue Hole as being peaceful and quiet. Previously, Finch described water as being peaceful and quiet in Chapter 12 (though Violet doesn’t know about this). It’s also worth noting that Violet shows how far she’s come by being willing to look for Finch at all. She knows she’s going to find something horrific and upsetting—but she’s not as afraid of difficult emotions anymore.
Violet takes off her shoes and dives into the water. She swims as deep as she can, but she can’t hold her breath as long as Finch could. Violet knows he’s gone, but she continues to dive for him. Finally, she crawls out and calls 911. Soon after, the sheriff, fire department, and an ambulance arrive. The family who owns the property mills around too, and the husband says, “Goddamn kids.” Violet knows he’s talking about Finch. Men dive into the lake. Violet wants to tell them they’re not going to find Finch since he’s made it to another world, but eventually, they bring up a bloated body. Violet refuses to identify it.
The novel has made it clear that “Goddamn kids” aren’t actually the problem—stigma and shame surrounding mental health issues, which can make a person feel like their only choice is to take their own life, is the real problem. Out of respect for Finch and to protect herself, Violet tries to tell herself that Finch got what he wanted by killing himself—that he made it to another world where he doesn’t have to be in pain anymore.
When the sheriff asks for Finch’s mom’s number, Violet says that she’ll call. Finch’s mom answers the house phone on the first ring, which enrages Violet. Violet says she found Finch where she thought she would and apologizes. Finch’s mom makes an awful sound, and after a minute, the sheriff takes the phone. Violet lies down and thinks of The Waves.
Only now, when Finch is dead, does his mom pick up the phone. Violet believes that Finch’s mom had numerous opportunities to help and support her son before it got to this point, and therefore seems to blame Finch’s mom (at least in part) for his suicide.