Is it okay to date your friends previous "situationship" ?

So the hit tv show Grown-ish came back from it's fall break this past Wednesday on June 5th, and if you are a fan of the show you know it left off with some drama. Let me fill you guys in a little, Zoey ( Yara Shahidi) and Aaron (Trevor Jackson) were in a situationship, he was her crush when she arrived to college, they have been on plenty of dates and have hooked up. He has also met and chilled with her family. Now while she was dating him she was dating another guy Luka (Luka Sabbat). It took Zoey a while to pick out of these two guys to be in an official relationship with, in the end she chose Luka. Now let's fast forward to season 2, Zoey and Luka are in an official relationship, and Zoey's best friend Ana (Francia Raisa) and Aaron have started to spend more time with each other and slowly but surely have developed feelings for one another. It's starts off as an attraction at first but then turns into something serious, so serious that they end up having sex. Aaron accidentally slips the news to Zoey and of course she is upset. Ana tries to apologize and says technically Aaron isn't her ex, (which is true). Zoey says even though that is true Ana knew how serious her feelings were for Aaron and that if she felt like she wasn't doing anything wrong why did she sneak around? Zoey then decides that they aren't friends anymore. Now my question to you guys is who was wrong in this situation? Before the episode aired I cant lie me personally I thought Zoey was just in her feelings and shouldn't be upset because she didn't choose Aaron when she had the chance and now that she is in a happy relationship she shouldn't be bothered because they technically were never together. That was until I talked to my own friends and got their opinion. One of my friends had an interesting quote that stuck to me, "You being my friend I expected more from you and for you not to hurt me, and now I wont be able to look at you the same." I have to say I agree, your friend shouldn't even be thinking about someone you were in relations with period. From a real relationship or situationship etc. So I have to be #teamzoey with this one. Let me know what you guys think.