I agree, and I am very impressed that you're able to be so open and honest with us AND yourself. So many times we can't see the patterns! So many times we can't be honest with our part in things. I had the WORST time in relationships for quite awhile, and finally I realized it was b/c I wasn't being the best person in MY part (I was the "other woman" casually a few times, though I never tried to do that, but I'd believe guys when they would say they were single, ugh, and then I'd get "hooked" on the doofuses and stick around).
But it took being able to look at myself truthfully, and it's part of why I'm honest about my past, before I was able to truly move forward.
I see good things in your future, that you are so honest about this.
I think the trip, and reinventing, is a GREAT idea. But I do highly recommend that you take everything you value (pictures, your jewelry, etc) and put it someplace safe. With a friend, in a safe deposit box, in a storage unit, so that you can breathe while you're gone, not wondering what he's doing.
And this is just my opinion and experience...but if you guys try to move forward, letting him come and go is exactly what NOT to do, if he's there. DH and I had problems while engaged, and he moved out. That's how he had his space. We were BOTH willing to do counseling (he started doing his own counseling, and realized quickly that "I don't love you anymore" actually meant, for him, "I don't love myself and I'm scared"...it was only months later that we started couples counseling) and had to set up groundrules.
For me, to feel safe enough to put my heart out there, the groundrule had to be NO DATING. Neither one of us. I couldn't ask him about what he discussed in his therapy (if he wanted to share he could, though), and we had to be honest with each other about our feelings, but we couldn't tell each other where to go...except for the no dating thing.
And for us we couldn't have done it if we were living together...the day to day stuff was too hard on top of the deeper issues.
So I guess I"m saying two things.

One, don't dictate where he goes, but he doesn't just get to be a free spirit, either! If you are both interested in counseling (and I would recommend he go to individual counseling, and you do as well, with a DIFFERENT counselor, well before you guys start couples counseling (with yet another counselor IMO*)), the rules have to be set up and there has to be enough trust on both parts that you will both keep the promises.
*A friend of mine was blindsided one New Years Eve, and they did their counseling with the same person. As a result, neither of them ever felt safe, because they were worried about the counselor taking the other person's side.
Sidenote, based on the friend I just mentioned...you might find your health getting a bit better. My friend had chronic idiopathic autoimmune problems (hepatitis in her case) from the time she was 13, and after she finally allowed for the divorce plans to be set in motion, she got SO much better. She had a good 3 years of not being on the transplant list, not being yellowish, etc etc. Her husband, though she denied and denied it, had become a drain on her emotionally and mentally, and her body was failing partially because of the stress of it all. So watch for health changes!
I wish you the best, and I'm SO sorry you're going through all of this.