The age part was about Ian rejecting her and she going for Jeremy, not the videos. I LIKE TO THINK that someone more mature doesn't behave like that when rejected, also age sometimes doesn't reflect maturity but you know what I mean. The videos part I find even more disgusting when they are just fucking and not in a relation but as I said, I'm old fashioned.
Also, in the bar Ian not kissing her doesn't necessarily means that he's rejecting her or not giving her atention when she is talking to Jeremy. It's actually something I could do irl to see what her real interest is. As someone said, on chapter 3 they have more chances and also when she invites Ian and not Jeremy to go on a vacation. Imo her behaviour was despicable.
I inserted myself in this conversation because people here were making her some sort of saint and that, imo, couldn't be firther from the truth, at least as how I see it. If Alison is a saint, what do you make of Holly?