Write your copy and move on
If there's one thing I've learned in copywriting, it's to not take things personally.
Sometimes, it's hard. As a writer, every word you type is dear to you. They mean something. They're your voice. They say what you want to say, how you say it.
But with agency life, you can't get attached. You're not saying what you want to say. You're your client's voice. So you simply meet their brief and move on.
Creative work can take someplace else.