Yes, Alexis attitude can be described as "take no prisoners", "all is fair in love and war", she didn't hesitate to step over her best friend (and take a deceitful attitude towards the MC let's not forget) to get what she wants.
Again up to each individual to say wether they are ok with that.
Erynn is a very damaged girl just hoping for happier days.
She's very hesitant upon meeting the MC again and doesn't know what to expect.
Are they going back to how they were? What about that declaration the last time they talked? Uh he's kinda hot now huh... she's very confused...
She also has a somewhat unhealthy attachment to the MC.
Again up to each individual wether they want to play the "rescuing hero who is gonna save the princess" or this just screams "RED FLAG".
Why would Alexis pressure Erynn? She's none the wiser here.
She may wonder why Ethan is Erynn's agent still, but that's none of her business, if Erynn doesn't bring "Ethan complaints" to Alexis she can't really do anything.
For me the explanation why she doesn't tell Alexis(or her mom) about her problems is that she's deeply ashamed of what happened and what's still happening.
Even explaing to the MC the situation happened because the MC witnessed Ethan beating her, it wasn't a choice.
And honestly, trying to "even the playing field" through lies and deception, lies and deception against your "best friend" and the guy you "love" is really fucking low in my book.
Clearly you see no problem since you keep bringing it up as an argument, so... full steam ahead buddy

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