I am the same age as you OP.
I think maybe there is a combination of factors here. Firstly, its is just so blatantly obvious now that you are out of your normal surroundings, to see what a complete misery this man is. It seems that nothing is right, nothing is good enough, as there is just zero effort from his side.
You have been holding this relationship together for many years by the sounds of it.
The second factor is I think, is our age. To be honest I have had it with anyone who doesn't pull their weight, and the thing is that all of these things are very much highlighted now. I am done parenting my now young adult children. I have brought them up to the best of my ability to be able to function as good adults in the world. That was my job. Which I have now done. But then to have another lazy arsed adult just there, and having to parent him too.... fuck that shit. It is not happening, and now is my time.
I am divorced and very much single, and am not contemplating going into any other relationship..... because I am not putting myself into a position of having to parent another adult man.
I always think that writing things out really helps to see what you have just been pushing under the rug. It is just the same day in and day out, so that lazyness of his didn't just happen one day. It is a bit like the boiled frog situation where it is now just too much, you have realized that this is it for life if nothing changes, plus also the fact that your daughter is about to head out into her own life soon.
So this holiday was probably a good thing. As it makes things clearer for you moving forward.