You know, people should put themselves first, then they should put the people they love second. If somebody who said they'd be putting me second failed to contact me during a time like this, I think I would consider that to be too selfish and self centered - 30 seconds for a text you know? Sorry to be negative but I also would have to agree that he doesn't seem to have what it takes to be a good, honest, upfront partner. If he does end up without his wife and with you, and starts dating again (ya sure, its complicated so he wouldn't do it again - I wouldn't count on that though), those same issues are going to manifest themselves again in all the same ways if he hasn't done something to grow past them such as therapy.
I am sure people have mentioned this before, but full triad would mean you are dating her too, I've been confused in your posts since if you had been involved with her I have forgotten you mentioning that. What he wanted (I assume) is a V where both of you get along like gangbusters and dont cause him any stress. I only mention this because advice can be more useful if things are described accurately.
You say that if you lived together you'd be a full partner and "Being a full partner means sharing our lives in full." I want you to really think - if he isn't sharing with you in full now - ie he's still having sex with his wife and upset if you have the nerve to ask him - he's going afk for days, weeks or months at his whim without really caring how it's affecting you, and it's unlikely that it will magically change if you do move in together. Going incommunicado for months - how do you convince yourself that is part of love? 8 months ago you were talking about dating, I hope that you have been open to dating and going out with people.
I'd surely not think about moving to be with him until 6 or so months had gone by with him not living with her and you could see how his actions were going to be when he didn't have her to blame his behavior on.
Happiness will never come to those who fail to appreciate what they already have.