Listen. Ive been where you are (51, 22 years together) and with alot more net based women on his side, denied for years.
God knows, I do know how tough it is, and I cant answer your main question about getting the trust back- I havnt yet (but only 4-5 months since discovery).
BUT I would not take that rubbish eg the way he talks to you. He is wrong here, not you. If he had a problem with the relationship, he should deal with it by talking to you. Or he could have left, and then had another relationship, couldnt he?
I found it hard to decide to leave- I didnt leave, but I did get to the point where I would have, and THEN he changed radically, and still is a new man (or so I think).
Now dont get me wrong, the fact that it took this much to get him to be honest and to change his behaviour was no unnoticed by me. But I have decided to give him one chance. Most MNers thought I was mad.
But truly, I wouldnt take what you are taking, in terms of the current behaviour, let alone the trust issue, which he has not helped you to address at all through any real concrete reassurance.
I always was fairly confident, and able to argue back, it just never used to get me anywhere. And I do think these sorts of men, if they dont change, will have you questioning yourself all the time instead of them- I was in that situation, certainly.
You dont need to doubt yourself. He gets nasty if things arent done his way? If you let him get away with this, he is far more likely, in my view , to do it again, as he doesnt respect you as a person. Telling him top develop some respect for you, or do it himself, will get you further with him than any other thing you could do.
He has got your self esteem on the floor, hasnt he? No wonder you are on ADS.
Finally, what made me shift, finally, is the nurse I saw when I was trying to give up smoking (and I had shared some of my fears) saying to me,
"You can continue to do nothing. But do you want to be in this boat this time next year, or the next? Is it going to change on its own?"
It did make me see that it wasnt going to change on its own, ie just because I wanted it to, and I couldnt cope with it long term. And I finally understood that it would have gone on, and I was only coping by struggling through one miserable week after another, without any happiness.
I hope that helps, a bit.
Ps. Look at some assertiveness training materials online, too!