You have to be able to have your own time, doing something you love. It's important in every relationship that you have your own time. Maybe her problem is that she doesn't have anything to do during that time and so she's jealous of the computer since you're not spending all your free time with her because she has nothing else to do. It sucks, but that's likely the case.

With this, my suggestion is to see if you an help her come up with some sort of individual hobby she can do while you're playing a game. It could be something like bouldering, or maybe painting, or yoga. If you spend all your free time together, you'll start to hate each other.

She sounds unreasonable about the finances. You two are not ready to own a house. Rent a little longer & maybe see if you can move up in your company. You can't be expected to help own a home until you have money to save on your own. Also, my significant other and I split up our bills proportionally. If she can save x% of her income, you should be able to save that percentage too. The fact that you're splitting income and still having incredible issues is unsettling. It's obvious she's not satisfied with that. Maybe you can both go to a financial counselor (but this would cost money) to show her how much you BOTH can afford. Y'all need to talk, openly, about everything.