Am I Wrong????

This is kind of long but I really need others opinions on this situation. I am currently 29 weeks pregnant by my boyfriend. Our relationship is one that moved really fast. I only knew him a month before conceiving so we are still getting to know one another. I truly love him and we’ve had our ups and downs but I thought we were over most of those hurdles until now. I have two kids from previous relationships and he has none. My oldest is 19 and my youngest 7. Girl and boy respectively. Him and my son have been struggling to get along. He argues that my son doesn’t respect him but I’ve tried getting him to see that this transition is hard for him. (I literally just divorced his Dad last year before meeting this man, who by the way was just supposed to be a hook up. However, that’s another story for another time, Lol) I ’ve talked to both my son and him and I thought we were finally in a good place. He was visiting on Thursday and they were playing, which brought joy to my heart bc they were actually getting along. Well my son hit him with a sword and it accidentally hit him in the face. I saw the anger wash over him as he starts yelling and grabbing the sword from my son. I yell at my son for even hitting him with the sword, bc that material definitely hurts, as I’m trying get the sword from my boyfriend at the same time bc I know if he hits him with the sword he will hurt him. So he jumps up and proceeds to spank my son across his butt. All of this is happening in my room btw, I’m laying down bc I wasn’t feeling well but my son was over by my side of the bed. So I put my arm around my son and tell him that’s enough and that he’s only a kid. Well he proceeds to try and move my hand and whacks him a few more times. He then tells me that the only reason he did it the second time is bc of my big mouth. That I had no business saying anything. We proceed to argue bc I tell him there’s nothing right about what he did. That I probably could have gotten over the first time, but the second time no. And for you to openly admit that the only reason you did it was bc of me? Well hit me. Don’t take you’re anger with me out on my son. He tells me to never correct him in front of my son or yell at him in front of my son again. You’re yelling at me in front of my son so I’m going to yell back. I tell my son to go to his room so that we can have a talk, at which point my boyfriend then storms out and says he doesn’t want to talk to me. He leaves so I call him on the phone in disbelief that he actually walked out on me in this serious situation that we need to fix. He goes off on me on the phone, calls me stupid and hangs up in my face. I am in utter shock. This is a side of him that I did not know existed. I sent him 2 lengthy text messages letting him know that I will always be a Mom first and my job is to protect my kids. I’ve told him from day one to never put me in a place to choose between my kids and him bc my kids will win every time. Well after he hangs up on me, I proceed to block him bc I don’t play when it comes to my kids. Next thing I know, he’s at my door knocking but I don’t answer bc at this point there’s no reason to. I sleep on it and reason with myself that at some point we have to address this bc I’m having a baby with this man. So I unblock him but I’m truly hurt. He calls a few times but I’m not ready to talk. He sends a couple of messages but I don’t respond. I finally text him yesterday morning about what I was feeling. He texts that he understands and that he loves my kids. I also let him know that when my son tells his Dad what happened that I can’t support him when he’s wrong. That I really don’t need that kind of drama in my life right now but that we’ll cross that bridge when we get to it. He finally calls and we have a conversation. Well more like he had a conversation bc he just fussed at me telling to me to respect him as man, never to correct him in front of the kids and to never get onto the kids in front of him and never to raise my voice to him in front of the kids. There was another situation last weekend but it wasn’t physical like this..........it did raise a red flag for me but then I chalked it up to he had been drinking. Well he brings that situation up telling me I was wrong then too. Apparently everything is my fault. Again, I will never support you when you’re wrong. If you’re yelling at me in front of the kids, I’m yelling back. I’m going to correct my child when he’s wrong, right then and there and if he’s doing something to the kids that I don’t agree with, I’m going to address it as well. He goes on a rant about us raising my unborn son and how it’ll be. I let him know that it doesn’t matter if it was his son, that my response as a Mother would still have been the same. We argue back and forth, I cry bc I can’t fathom how he can’t see the wrong in this situation. He tells me that we can’t live together like this and if I don’t respect him and how he disciplines the kids. But again, I can’t support you when you’re wrong. No matter what I say I can’t get him to see that he was wrong, especially what he said. He calls me on his way to work this morning just to bring up this same argument again. The only difference this morning is he threatened to hit me. He told me if I talk to him like that in front of the kids again that he will hit me. That he has no problem disciplining me. I’m like wait, what? Discipline me? I am not your child. I am an adult just like you and if you hit me in front of my kids or anytime for that matter, be prepared to get hit back. I am adult just like you. He wants all this respect and to be treated as man, but beating it into someone or pushing fear onto them is not the way to get it. That conversation was done. So I’ve sent a message letting him know how I feel. I’ve gone along with a lot these few months but this is one thing I can’t go along with and pretend is ok. I even try to make excuses for him that it’s just his culture or that he doesn’t have kids and has never been around kids like that before so he doesn’t know. Well I can’t do that anymore. I love this man more than words can express........we’ve even been looking at houses together so that we can have that family together that we both want, but what now? How can I have a baby with a man that doesn’t respect me or my kids? Not only that but he’s said some things about my 19 yo daughter that were disturbing to me. I always address it but he never sees it as wrong, so again, I try to chalk it up as a cultural thing. I can’t live my life like that though. Please give me some advice bc I don’t know how to move forward with someone like this. But at the same time, I’m terrified of bn a single Mother for the 3rd time, which if I’m honest with myself, is why I’ve put up with as much as I have. But we’re talking about my kids now and Idk what to do or how to make him see or understand how he was wrong. I’m rambling at this point bc I’m kinda scared to hear the truth. Ppl on the outside looking in normally see things that you don’t and have a clearer view. Anyways, thanks if you’ve read this far and if you can help in any way.