I didn't think that you thought you were piecing, I agree that you seem on pretty solid ground there. I was more saying, "noooooooo!!! don't fall into the trap of thinking you are piecing again," because it seemed to me that you were getting encouragement to do so.
As for the rest, you had recently said pretty much that playing the "just friends" or "casual date" role wasn't working for you and that you were not going to do it anymore. If so, then it is best to simply be direct and honest about it.
If instead you want to accept things as they are and give the R a chance to grow, well then, give it a chance to grow by stepping back to a level of commitment/interest that matches that of XH. That doesn't mean giving up, it means accepting reality and building an R based on that reality, and giving XH some space to invest in the R himself.
You carried the big thing to work yourself and didn't give anyone a chance to help. If you carry the R yourself, you don't give XH a place to make it his R too.
