What’d I Do?
Moving in together means more contact, and sometimes more contact means more friction. When you argue, you want to be in your tight, but when things begin to escalate, you really don’t care who is at fault. You just get tired of the cold war and you need it to end already. Eventually, someone has to give in and take responsibility.

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Even if you think your anger is justified, your girlfriend might accuse you of things you weren’t even aware of. Maybe you don’t have to apologize as quickly as this person did, but apologies would be needed. If you’re not ready to apologize, then you should be ready to forfeit a few good times with your gist buddy.