Sometimes illusions are deadly because what we think of a person is oft times not always what they perceive in reality. I enjoyed this write because it is unique. The wording you used especially.
When we think a lot of times anxiety comes into play and that is the feeling i get here with my statement above we create scenarios that are untrue in our minds. You wanted to feel this person's emotions in you but in the end you had to breathe them out because they were causing harm. They took a piece of you.
You always felt something was missing or wrong and with this person's illusions it made you feel worse. They somehow completed you and made you whole again.