Well, don’t be too hard on yourself.
Statistically, around 90% of those who plan to thru-hike do drop out. So, you are not the only one. If 9 out of 10 people do drop out then that’s an overwhelming majority of those who start. But, look at the bright side, at least you did 100 miles or so. That’s way more than the average American does. And when you talk with most people about the AT, they frequently comment that they always dreamed about doing it. So, at least you have done some of it.
You didn’t elaborate on why the 100 miles kicked your butt. (I hesitate to call it a wilderness when there are so many gravel roads crossing it and nearby). I suspect that most people don’t fully realize the work and effort required to do a long distance hike. They lack backpacking experience, and don’t have the mental attitude needed for a long distance hike. Hopefully it was a learning experience for you, and now that you know more, you can be better prepared should you decide to go back and continue.
So, how to deal with it? Well, someone once wrote or said never quit the AT when you are tired, grubby, and hungry. Get cleaned up, rested, and have a good meal. Then, think about all your reasons for wanting to do a thru-hike, and figure out if the reasons are still valid.
But, you are off the trail for now. If you still have the desire and interest to continue, then start planning how you are going to make the next hike better. And, if you enjoy hiking, then go out and hike something less grand, either on a day hike basis, or shorter section hikes.
But if you at totally burned out on backpacking, and think that backpacking isn’t your thing, then turn your gear into cash, and find another interest.
Don’t know if I made sense or not. Hopefully you aren’t too hard on yourself.
Peaks