Vulnerability isn't weakness. Self-compassion isn't self-pity. Beating yourself up isn't discipline. Grief isn't failure. Doubt isn't betrayal.
Repeating this one more time, mostly for myself.
This is going to take a slightly different tone than everyone else's (excellent) support. And I, like Pix (sorry you're low, Pix) am feeling a little low myself, so it might not be the appropriate things to say. So, Maria, if you're in a different space this morning, feel free to ignore.
But I guess what I want to say is that I know that while you are indeed loved and lovable, I also know that our support is not the same thing as love from a husband. You are allowed to grieve that you don't have that anymore.
And you are allowed to wonder if you ever did. I think you probably did, although maybe not in the form you wanted to or should have. But I'm sitting over here in the desert. I didn't know Rob. But, and this is important, even if you didn't, even if he never loved you, you are allowed to grieve that too, just as much as if he were still alive. You are allowed to resent that, be angry at that, be mournful over even the fact that it's a possibility you have to confront. It's something you should have been able to have together, and if you didn't, then the point of realization about it is totally an appropriate time to grieve that loss as much as any other.
Now. Shoulds and woulds are what they are. Which is to say, not worth all that much. There are lots of shoulds that aren't, and that sucks. So grieve them. But then continue the work that you're doing (and you are doing it, boy howdy are you doing it) and you will, one day, have a new life that is the life you created and therefore the life you want now. Maybe not the life you originally dreamed of. But a good life that you can put together from your own rubble and build toward the future.
When it comes down to it, you and Rob were both flawed people in a flawed relationship, like every single other person in the universe. And now here you are, and it's not where you thought you'd be and it's not where you want to be, but you are still on your own two feet, and you are capable of getting through this. It has not been, and will not continue to be, easy. But you can do this, little at a time.