How do I leave peacefully but at the same time making clear I was hurt

So, I(18F) recently I had kind of a weird breakup with my ex (18F). There was no closure, no explanation, no guilt from her side. She just went and found someone else very quickly. It is very clear to me that she doesn't want me in her life anymore and that I am at most annoying her every time I try to talk. Despite this I still want to say goodbye to her in a polite way bc she still is very important to me. That said, I want to make it clear to her that what she did hurt a lot so she is conscious that her actions were not fair or respectful. How do I do that without it feeling like I want to attack her? I just want her to see that her actions have effects on other people. Regarding the exact actions she did which hurt, they are the following: barely prioritizing me as her partner(her friends being over me), not keeping her promises, treating me like a stranger several times, giving false hope and excuses, and leaving like I meant nothing all along.