Open a hard talk with what you want for the relationship, not a list of what they did wrong.

Opening with the charge sheet tells somebody instantly what kind of conversation this is, and from then on they are building a defence rather than listening. Saying what you are after first gives the whole thing a destination, so the complaints that follow sound like obstacles rather than evidence against them. Same facts, completely different conversation. People fight the frame more than the content.

Before the next hard one, write the single sentence about what you want and lead with it out loud. Keep your list to the one or two things that genuinely matter. Then ask what they want out of it.