Hard situation. I agree with anniebrooke. I know that my husband was weirded out when I was pregnant. He said something like he didn't want to hurt the baby. Hm. And I am not sure how into the big belly he was. Oh well. It all went back to normal after I had the kiddos. However, I was then exhausted so it actually was after our kids were well into the toddler years before we were all the way back to normal. Lots of guys do look at porn and it is meaningless. But I don't know your guy and the situation. You sound like he is not willing to stop which is always concerning. The brain can change on porn like it does drugs believe it or not. And if he uses it to emotionally escape, it's the very same thing as an addiction. Let's hope not. Talk to him again. When is the baby due?
Hm, some guys like pregnant women, because their bodies look more lush. Obviously your guy is not made uncontrollably horny by how a pregnant woman looks. Or maybe something else is up. Some guys are not turned on by the idea of having sex with a mother-to-be because it's too much "mother" and not enough playgirl. I knew a guy who divorced his wife a few years after she had their daughter, because he just could not see her as sexy any more because he firmly identified her in his mind as a mother, and to him, mothers are not sexual. I don't know if that is what is going on, but maybe that is possible if he is not even finishing the sex with you.
Guys look at porn for a quick hit with zero demands on them, not even for a cuddle afterwards. I suggest women shrug it off. Maybe he is feeling really worried about the future and your and the child's demands on him. Porn might provide an instant release with nothing expected back.
From your end, though, this seems to have become this huge wild swirl of promises and supposed betrayal, with swearing on the baby (why on earth did you make him do such an idiotic thing?) and all the other drama you named. It sounds like to you, watching porn is cheating, full stop. Well, for heaven's sake, it is not. Snooping through his phone is a major betrayal of privacy. Him looking at porn means nothing.
Anyway, do you want to break up over this not-really betrayal that until he met you, he probably would never think of as anything but normal? Do you want to make your way through life trying to find Prince Charming who never would look at porn? Maybe you could find a guy with major sexual inhibitions, or religious convictions against it, or just someone who is a good filmmaker and feels porn has poor plotting, lighting and production values. Or you might just find a garden-variety guy, who happens to every now and then gin up a porn video when he wants physical release or stress release.
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