1. Break up over text messaging one month prior to actual breaking up. Sure, you'll think it's really over, but then when you find yourself at his apartment in a month, explaining the same things you spoke about in person, you'll realize how foolish it was to assume anything.
2. Explain, face to face, that you cannot see each other, talk to each other, sleep with each other, etc. ever again. There are new people in your life, there are new opportunities, and this guy is toxic. Have a nice, albeit drunk, conversation about not doing it. Like, ever again. Then pass out on the top of his comforter.
3. One week later, proceed to get enormously drunk, respond to his texts, go to his apartment, turn him crazy on, and basically leave him in the dust - angry, shouting, threatening. This way, the deal is sealed - he will never call you or even look at you in public again.
Hallelujah! Free at last, free at last!