If you have a TV and a game console, you can do a special activity with her. Playing games with her will increase her liking and help her manage her stress. Of course... if you win too much, it will backfire and increase her stress, so it's best to lose in moderation.
There are two games you can play.
Gomoku
A two-player game. You start with the white stone and she with the black stone. Note that she's not very good at Gomoku.
For those unfamiliar with the rules of Gomoku, it's a game similar to tic-tac-toe. Players take turns placing their stones on the board and the first player to get 4 or 5 stones in a vertical, horizontal, or diagonal alignment wins. Find the rules to learn more
Planet Eater
Planet Eater is a snake-style game. You play as a Giant Planet Eater and grow by eating the stars on the screen. However, you're limited by an increasingly narrowing field, so you'll need to eat as many planets as you can within the time limit to score points.
Planet Eater is for one player, but you can also play with her. In that case, she plays first and you play second. If you score more points than she does, you win.
Depending on the outcome of the game, her stress and likability goes up or down. If you win, her stress goes up. If you lost, her stress goes down. However, she doesn't like it when you lose too easily, so you'll want to win or lose in moderation.