The blubbering like a little sissy isn't a good place to be. I get it, I was there too once. But spending 30+ minutes with the ex while dropping the kids off isn't good for you. If you can't handle it, cut it short. The kids don't need to see daddy whimpering either.

Your emotional state suggests that counselling or therapy for you might be useful. But my number one takeaway is that you're living in the past. You talk about being invested and not wanting to lose it, but you're viewing all this through the lens of the past, not the lens of the future. I heard a great quote the other day that memory in humans did not evolve simply for the purpose of reliving events over and over. Instead, it's there to use to extract lessons for the future to improve your actions, and once you figure out your lessons you can let the past go. The mindset you need is NOT one where you look back on what you had and try to undo the past. That ship has sailed and all you will do is create a feedback cycle of desire which will never, ever, provide you with any satisfaction. Instead, look at where things are now, accept that that's the way it it, and figure out what you can do to make your future and your kids future better, and start doing things that line up with that vision. All you have is now, circling the drain of the past over and over isn't helpful. Sunk cost fallacy and all that.

There are good reasons that you've been linked to Rollo's "garbage" article. Trying to engage in a course of action and only being satisfied with the outcome (reinstate your marriage WTF) when that outcome is contingent on the decision, free will, and desires of someone else is ultimately a recipe for frustration and failure. You're much more likely to create a satisfying and fulfilling life by planning to engage with your kids as a dad to the best of your ability and bettering yourself - by now you have obviously seen a lot of the dark corners and unattractiveness in your mind as it is today, and working on that for it's own sake will lead you to a much better place than chasing something outside your control

I'd also question what makes you think you can give effective advice on asktrp when you're in such a state as you describe. That sounds inauthentic to me, and I'm sure at some level you know it is too, and behaving inauthentically will only lead you to distrust yourself even more.

Best of luck to you.