Tips on breaking up when you’re a people pleaser

I’ve always been a huge people pleaser, and I still am. Me and my boyfriend have been together for almost a year, and I’ve thought about breaking up from time to time throughout our relationship. I feel like I have already lost interest in us and have given up trying to face/fix our issues because I don’t see us working out. It makes me really sad because I really thought he was the one but i’m always left disappointed or dissatisfied. I know that my boyfriend struggles with mental health issues and all his friends told me how they’ve never seen him as happy as he is now with me. It breaks my heart to know that i’m gonna upset him with breaking up and probably make him isolated and depressed again. I also know that my boyfriend jumps from one relationship to the other and never takes time to heal after a breakup. Mentally I have already broken up with him, it’s like we’re not even together in my mind, but physically speaking I can’t even get the words out. Every time I have tried to talk about how I feel, I always tear up and end up not saying a word. It’s been two weeks since I made my mind up about us not working, and everyday I want to tell him because he doesn’t deserve to be in this situation, but I physically can’t get the words out. His birthday is in two weeks and I can’t stand the thought of him being sad while celebrating with his friends and family. I wish that our situation was different or that I was more brave. I feel so stressed and hopeless because I keep dragging it out, but I feel horrible about breaking up because that’s the last thing I wanted for us.