Chaos Theory by Nic Stone

Scars exist to remind us of what we've survived. . . 

Since Shelbi enrolled at Windward Academy as a senior and won't be there very long, she hasn't bothered making friends.
What her classmates don't know about her can't be used to hurt her - you know, like it did at her last school.

Andy Criddle is not okay. At all. He's had far too much to drink. Again. Which is bad.
And things are about to get worse. When Shelbi sees Andy at his lowest, she can relate. So she doesn't resist reaching out.

And there's no doubt their connection has them both seeing stars . . . but the closer they get, the more the past threatens to pull their universes apart