I think this is intentional -- both Ian and the player can get a feeling Cindy is dragging her feet with breakup with Wade for some reason, and then comes a talk with Ivy who mentions that there's rumors Cindy is now dating Alex, which seeds further doubt in Ian (and player, too) Ian's thoughts on that are like they were copy/pasted from arguments in this very thread: "
no, she wouldn't... but then she cheated on Wade with me, so she might do it again now"
Ian and Alison can have potentially a big development, having sex for the first time. Also, fucking Alison explicitly sets a flag Ian is cheating on Lena, so all these people complaining how Lena can cheat on Ian but not the other way around, can sit down and shut up now