If you marry, your parents will be upset and it will take time for you'll to heal. Your in-laws don't have the right to request add-ons or to remove things as they are not paying for anything. As for your fiance if he won't stand up for you now, he won't stand up for you after getting married. Also have the feeling that his family will interfere in your marriage. This seems to be already a disaster and it will continue.
Dump her make sure she leaves the house for 3 days pack up her stuff yourself change lock on doors and put locks on windows make sure to take the stuff you bought her and sell it to get your money make pack up her stuff send it to one of her family members make sure you include photos or videos of her cheating get her to Sign a agreement that she gets nothing you can do this buy hiring someone to pretend to be a delivery guy and And needs her signature for a package then get a good lawyer make sure she gets nothing from you then if you have the money go to Las Vegas for a vacation then go on a date
He wasn't giving her the attention she deserved since his schedule was work and then go home and be addicted to videogames 😂😂😂, the day is super long, maybe he was working a max of 8 hours daily and then? probably playing another 8 hours of videogames, impossible to make a relationship work with that behaviour... I'm surprised if she got a call with the way he acted or he just dropped her text msg and forget about everything til the next day!!!
Cut ties with both of them, the fact of having a deep depression means nothing, you are still aware of your acts and obviously will have to face the consequences. This poor guy is such a victim.
I don't think that's the case, in the long run if her masters degree works out and she actually works at the end of it she will be bringing home the most money, until then it's anyone's guess.