help me write a paragraph telling my ex how boring it is been a spare wheel in his relationship while you don’t know.. it should be RUDE to him

I just wanted to let you know how utterly boring and pathetic it has been being the spare wheel in your relationship, always on the sidelines while you flaunt your affection for someone else. It's nauseating and insulting to be treated like an afterthought, like I'm just there to fill in when you're feeling lonely. Well, I've had enough of being a second-rate option in your sad excuse for a love life. I deserve better than being your last resort, and I won't settle for being treated like garbage any longer. Goodbye and good riddance to your sorry excuse for a relationship.