Advice on break ups 😕

So I have been with my boyfriend for about 2 years. He cheated on me and has lied countless of times.. but I always end up forgiving him. Tonight was the final straw. He didn't cheat or lie. It was just more arguing. He called me at work pissed because he saw on Facebook where I was planning on going out to eat with a group of friends. There would be 2 guys involved but I have known both of them since I was young. Anyways he called and I tried saying "I'm at work can I talk to you about this later" and he SHOWED UP TO MY JOB. Anyways we made up and he finally left. I told him I wouldn't go. I have lost so many friends because of him. But I'm scared to break up with him because he was my first boyfriend. I'm 19 years old. And I have always been overweight and struggled with acne. I guess I'm afraid to be alone? I'm not sure. My mom and I were talking about it. How do I break up with him and NOT give into him. Has anybody been In a situation like this? I really need advice. I'm in college and working a full time job. I can't keep dealing with the stress he brings on top of it all. Thank you so much