You are ready when you are ready. You are a smart man. You have your ducks in a row, consulted an attorney, and have a therapist. You are moving at your own pace, and that is as it should be.
And heaven's yes there are those of us that have been right where you are. If we took a show of hands regarding who filed for divorce, and then later put the breaks on...well you wouldn't be able to see the ceiling with all the hands in the air. Don't get to mired down in self doubt. There is stuck, and then there are speed bumps. I think you have to much awareness to really be stuck.
I did exactly that. I don't have huge regrets with putting the breaks on the divorce, even though I went through with it not long after. In hindsight I wish I'd have just gone through with it but perhaps mentally/emotionally I needed that last dance to be able to fully move on. It is a horribly painful process and we need to be sure. We need to be ready.
My big regret is that my boundaries were so undefined and wobbly. I regret not maintaining an emotionally safe home for my kids and myself. That is not easily undone for any of us.
Be gentle with yourself right now. You are human and doing the next right thing sometimes changes.
Be kind and honor yourself. Know your boundaries and protect them. Fight to keep your home, your son, and your inner self *safe*. You do not necessarily need a divorce to do that.
ETA: Don't get mired in the details. I don't even remember the day I filed. I don't even remember the exact day the divorce was final. I spent a couple of *years* waiting for the next important event or day to come and go. Not very smart. My kids are much older and while they have a lot of memories that are not good, I doubt they have an inkling about the details.