Starant - do you have at least one close family member you can confide in? a good friend? a counselor? even if you journal, it might help to get your feelings out and your ideas down. And you have us too, there are so many people here, with different perspectives. We may say different things but we all do care and we want to help, each in our own way. I don't think it will ever be enough with what you're going through. The mindfuck (I hope you don't mind but I do swear occasionally) your husband is putting you through is something that makes you want to shout it out to the world just to assert and reclaim your sanity. This man is driving you crazy. I don't know, of course, what he was like before this affair but since this started, he's a nut. Like so many, if not most of them in affairs, they say and do things that don't make sense because they want impossible things. They want the safety and security of the marriage, they want to be with the spouse and children - but they also want the excitement and newness of the affair and the feelings that bring and the experiences.....BUT YOU CAN'T HAVE BOTH. You can't have safety and excitement at the same time. We have to make choices in life. If he refuses to make choices, then you have to make them for your own safety and security, for your own peace of mind. Even if you didn't have a child, you'd need to do this FOR YOURSELF. NO ONE has the right to treat you like this for any reason. You are a precious person with your own strengths, and goals, and feelings and value and no one should be allowed to shit all over you for his own selfish desires, whatever they may be. That is an ABSOLUTE.
He says shit to you, but I wonder what she would say if she heard how he views HER....as something to use sordid porn techniques on like a blow up doll. That's disgusting. I don't know what started this in him, I think modern porn is very very malignant and puts some really bad ideas and desires into people's minds. It's not "normal" sex anymore. A lot of it is violent, coercive and degrades people particularly women. Someone can't watch a steady diet of this crap without having their mind and soul twisted.
So he thinks he can have both at this point, this is called "cake eating". It's like having your cake and eating it too, which no one can do. And then he is erratic because he wants both so he goes back and forth. He says mean and cruel things to you because he wants to rewrite the marriage history and cast you as the villain as that means HE doesn't have to be the villain - you deserve all this! - and he's also trying to break up the relationship by being mean and rotten. And of course, he lies to protect himself and to create the image of himself he wants to have and project to the world.
You can't live with this, it drives people insane. There's a great old movie I often recommend from the 1940s called..."Gaslight"....it's where the term is from and it's the classic example of how a husband drives his wife mad, even though he may love her in some way because there's something else he wants more and he can't have both. He would destroy her to get the other thing he wants more.
What your husband is doing is crazy making and I'm not sure you need a lot of people to talk to right now, what you probably need to do is make up your mind and move forward with divorce if you haven't already. This isn't going to get any better, he will drive you more and more crazy and you will get weaker and more unhappy and sicker. The best way to end it is to end it - nobody wants to but you have to save yourself - both for you and for your child. Mama can't be driven crazy like this. Your child needs a sane YOU - Dad is inherently unreliable.
I think once you find a good lawyer, if you haven't already, and actually file for divorce and start putting formal, legal limits on how he acts with you and your child, you will start getting your power back and feeling better. The only way to end it is to take action. And recognize that it is NOT YOU who is crazy, or defective or wrong in this situation. THIS IS TOTALLY ON HIM BECAUSE HE CREATED THIS AND HE'S USING IT TO MAKE HIMSELF FEEL BETTER ABOUT HIS CHOICES. He's immature and apparently NOT marriage material. Don't go along with this.
Once you file try to have as little contact with him as possible, you can work out a schedule of child visitation, my guess is he won't stick to it anyway, but try to cut down your involvement to text messages, emails or a scheduling app - the lawyer can tell you about this. Don't do recon or counseling with him - only yourself, don't visit social media, don't have him at the house or have phone calls. Try to keep everything as cut and dried as possible as if you were dealing with a stranger who might back stab you. Because this guy is a stranger now. Divorce, as hard as it seems, is not only the best solution at this point, it's the only one, especially if you want to save you and your child. Time to toss the man baby out of the life raft! Life will get better for you after you file and you will regain control over your life and your emotions. You need stability and security and right now only you can give that to yourself. Cut him out as much as you practically can and don't listen to any of his bullshit and whining.