If you initiated the divorce, you had reasons why. Remind yourself of them when you feel like you're maybe making a mistake. Be honest with yourself. I was in denial my whole marriage about how bad it's been, but now, I can see it so well. Maybe even write down the reasons you want the divorce and then in another column, the things that are making you think it's a mistake, and really weigh them.
For me, I keep thinking of this one time when my husband and I were trying to sell at our failing business, and we were outside, and it was hot and there were bugs, and my husband as usual was all into his phone and ignoring me, and I had thought, is this going to be my life? Every time I think I am sad it's ending, I realize if I could somehow convince him not to leave, we'd just be right there again. And I could not take it. So, maybe think of a time when you were so miserable you thought you'd be better not in the marriage, and then remind yourself of that when you feel any doubt.