Continuing from last time...
Stay on point. When she complains about your dirty dishes, maybe you have a complaint too. You might leave dirty dishes in her sink but she leaves wet towels on the bathroom floor. That is irrelevant to the conversation. Yes, it’s a slob’s behavior as well, but it is not the present topic of conversation and you’re only bringing it up because you feel defensive. If you have a complaint, address it later. Right now the topic is dirty dishes and what you can do differently so that she doesn’t get annoyed.
Remember: In most cases whatever the argument is you probably had a part in it too. Maybe she was the one who left the dirty dishes in the sink, but you didn’t need to yell at her for it or accuse her of being a slob or accuse her of not really caring about you. Apologize for the part you had in causing the argument.
Be explicit. Just as you shouldn’t be mind-reading and thinking that you know what her intentions were, don’t expect her to know what you’re thinking or what your intentions are. Be direct. And paraphrase back to her what you hear her saying. If you don’t know what her intentions were and she isn’t saying, ask.
Be clear about what it is you want. She leaves dirty dishes in your sink and that’s a problem for you? Be concrete about what it is that you want. Do you want her to wash them and put them away as soon as she’s done with them? Do you want her to put them in the dishwasher? Do you want her to take care of them by the end of the evening? It’s like when you write a letter to a company that ripped you off. You can write and complain about the pack of batteries you bought that were all dead when you took them out of the package, or you can complain and then end your letter with a statement about what you want in return for your trouble (a coupon, a cash refund, new batteries mailed to you). If you don’t ask, the complaint will be read and the company will do nothing. Ask for what you want. Do not assume she knows what that is.