I've read a lot of threads here, but this is one of the most captivating and fascinating. A few thoughts that came to my mind in reading about your present situation:
1. dday101798 is giving you good advice. Listen up.
2. There are success stories here that were achieved in situations similar to yours. There is hope (but a lot of hard work too).
3. When you left your H, it changed everything, but you don't seem to fully recognize that. Take this "being late" thing. When you left your H, that made a big statement to him about your ability to be "inconsiderate". Now, I'd bet he's watching to see if you've changed. Whether your intention or not, the message you sent was, "My Monday evening routine is more important to me than you are. If it comes down to being on time for you or going to my regularly scheduled gym night, I'm picking the gym." That's reinforcing his current view of you ('course if that's what you wanted, you're doing great!).
4. Your H doesn't trust you. Like many who walk away from a M, you don't seem to grasp the utter destruction and long-lasting impact of your act. Trust is a requirement of any working relationship, but checking out leaves it in tatters. This mistake can be overcome with time and care, but your apparent frustration with the pace of progress suggests that you expect to (largely) pick up the relationship where you left it off. That's not how it works. Consistent action, restrained response, and lots of time will be required. Consistent action provides the basis for rebuilding trust. Restrained response proves you can take the heat without bailing out like you did before. Time proves it's not just talk. Without these, your chances of success are substantially reduced.
5. Stop and look in the mirror. What you're feeling now is probably similar to what your H felt when you left. How do you like it? Now use that to understand why he may not be welcoming you back like the prodigal son. Give him the time he needs to work through the issues you left him with. Right now he figures he's better off without you. Nothing you do or say should reinforce that belief.
6. Avoid being the grape. You've probably heard the one about the grape that got stepped on...it let out a little wine. You say, "I've had a streak of bad karma lately and to make a long story short, my ex doesn't even ask if there's anything he can do to help." It's OK to say that here, but don't say anything like that to your H. My guess is you've given him a few reasons to whine about you, too, so if you open that door, be ready for a lot of return fire (and the loss of a month or two of progress in your situation).
7. Take heart. You realized your error before you'd wasted ten years of your life chasing a dream that never existed in the first place. Some WAS' blow a decade or more going from one bad, empty, or dysfunctional relationship to another in search of the elusive perfect person and end up with a life that's no better than what they left (if not worse) and an Ex that's long since moved on. At least you have a shot.
Not only that, you and your H still talk (even if it isn't all roses and violins) and you're even considering a trip together! Some folks here would kill for that kind of opportunity. Of course, what you do with it is up to you, but I'm optimistic that you may join the all-too-small ranks of those who came, who saw, and who conquered.
