Your take has one slight mistake, Andres was the one who broke up with her when told that she was pregnant from another guy(the guy he hates), so she can't be blamed for that, Andres ended things opening the path for her to scoot her way back to her number 1.I am not sure Emily is perfect. As I see it, after Santi left her she went for Andres as a rebound. She broke up with Andres with the first possibility of being back together with Santi. Inviting Mel, going to a bar which surprisingly Santi was hanging out with his friend, then tease the hell out of him. Invited him to the pier and all the cuddling, touching etc. remember how happy she was. Then when pregnancy thing did not brought Santi back, she took back that idiot Andres. When her path crossed with Santi again, she started seeing him again even though it made her "husband" angry. Should not she consider what was Andres feeling a little bit, if she cared him even tiny bit? She even said after Andres got angry, she kept seeing Santi secretly. Why the secrecy if nothing was going on? When MC reached to a certain age and she no longer needed Andres, she gave him the boot again. Also a while back I posted a pic of Emily carried by Santi while Mel present, if we consider that is not an error on Nyx's part. Then even after Santi leaving her stranded, his parents tried buy her out she was happily hanged out with Santi. Whenever MC did something she always reminisced of Santi but whenever topic came to Andres she was indifferent at best. She even admitted that she will always love Santi because he gave her MC but she said I don't fucking care what Andres does we are divorced for a long while even though Andres did raise MC. Even after their divorce he looked after him but she was quick to dismiss that altogether. Santi was nothing but a sperm donor but she always spoke highly of him and Andres literally gave his lifetime and she was not even grateful. She literally mentioned once and that was it, all the other times she talked about him like he was a devil. When she said Andres is not your father to MC, remember how irritated she was each time MC called Andres his father. The resentment was disgusting at best. He maybe not his biodad but dude fucking raised him, last 5 years as a single dad but she could not even handled MC calling him dad. Everything Andres did was nothing to her. I still disgusted how happy she was when she learnt Andres cheated on Nikki's mother. She immediately asked her number, offered her help but she did not get her number to congratulate before the wedding. Emily is one of the worst character in all AVNs, being hot does not change this fact.
Unfortunately for her Santi froze and bailed and she had to go back to her backup Andres...
Other than that, i'm with you, what Emily does is dodgy as fuck... but Nyx always falls on the side of women and i highly doubt she'll show Emily as a cheater who broke up a relationship with a man that was in the right.
The game wants to portray this thing as "Emily did this innocently and Andres overreacted", not "cheater Emily broke up their relationship" even though it's a situation that is at least suspicious as fuck, and disrespectful of your partner...
And to finish things off Nix added a "Andres was always a prick" for good measure.
If you ask me her fear of embracing flaws and dodgy behaviour in women is one of Nyx weak points, in situations like this the game forces a bit too much to say "actually she's done nothing wrong", things like "completely innocent" secret meetings with a former lover strains believability.