“For him she planned sugar in his motor, scissors to his tie, burned suits, slashed shoes, ripped socks. Vicious, childish acts of violence to inconvenience him, remind him.”

Alice’s revenge is the kind of revenge you have upon someone you really love. Of course you don’t kill them. That’d be counterproductive. There’s little suffering in killing. But to constantly remind them of their wrong-doing – that’s how someone really suffers.  To find ways to let them know every day, multiple times a day, just how bothered you’ve become by whatever wrong they committed.
It’s dramatic and it is childish and it will frustrate whoever you’d do it to, but they’re the ones with the ripped socks and every time their toes poke through the hole and hit the inside of their shoe, they’ll be thinking of you.