Well, Blue tends to jump the gun. While it's 'possible' that your husband has been with other women, to automatically assume he has, and to proceed forward as if he is already guilty, is nothing but judgment. This is down to each individual. For some it may be that they have not progressed that far, for others it may be something they never do. As always making blanket statements about people leads to nothing good.
Your husband is likely addicted, and therefore needs to be treated as an addict. One of the most common misconceptions wives of porn addicts have (and it makes total sense to feel this way) is that they aren't 'enough' for their husbands. Your husband married you because you Are enough. But he's been mislead by an industry whose entire focus is creating illusions that are more appealing than real life. It's not actually a reflection on you so much as it is that he fell for the illusion and became addicted to it.
Now is this to say you just accept it? I'm not saying that at all. Your husband needs consequences and at this point only you and God have the capacity to enact them. If you have already confronted your husband and it's had no effect, then the next step is to discuss your separating and you, or him, moving out. For some men, the mere mention of this is enough to slap them out of their illusion. For others one of you may have to actually move out and live separately. Sometimes this works quickly, sometimes it takes a while before it sinks in. And, of course, in some cases, nothing works.
Even still, if he is phased by the threat or act of moving out, that's not the end. This IS an addiction after all. He needs to proceed to get counseling for his addiction and take active steps to prove to you that he is working towards Genuine change.
Before you even consider letting him back (or going back) you have to see steps being taken. And if/when you do move back in together he needs to have the understanding that if he falls back into his old ways then the next separation will be permanent.
Now take notice that a slip up is not the same as going back to old ways.
This seems to be the most common and effective approach. Or the approach that reveals the persons heart. It's either this or learning to just accept the situation for what it is. There is no easy, magic answer with someone who is refusing to admit or confront the issue. So you are looking at 6 months, Minimum, separated from your husband, and quite possibly longer. Rushing things will backfire.
As far as the lying and being 'hurtful' those are pretty vague concepts. Is he lying about the porn? Or is he lying about other things as well? If it's just the porn, then it makes sense he's lying. But if it's other areas as well, then that is a different matter entirely.
Same as being 'hurtful'. It's a vague concept that can mean many things. Such as is frequency, severity, reason (not that there is ever a good reason, but knowing why can make a huge difference in understanding what's going on), etc...