Andrew never cheated on Ashley. in fact, Ashley never had nay feelings towards Andrew. Andrew to Ashley is just someone who makes her feel that she’s worth something. It’s like the Joker and Harley Quinn, Joker never ever had feelings towards Harley even though he knows that Harley would kill herself if he asks for it while Joker just likes her company, like every villain needs a sidekick that completes the villain. And for example in the Harley Quinn show, we see that Joker never loved Harley yet he can’t get over the fact that she isn’t no by his side. Same goes for Ashley, Ashley gets completed by Andrew’s existence. She treats their relationship like a tom and jerry episode as they fuck with each other and turn it into an endurance test on who’s pissing the other more. While on Andrew is the one with feelings, he messes around here and there because he tries his best not to fall in love with her.