I started two "thru-hikes" and due to unforeseen circumstances prior to leaving came up short to adequately fund both. Like you, I saved money where I could, but spent freely where I desired. I was able to complete about half the trail in both instances. Got home, found a job and saved to finish the following year. It worked out really well as I met twice as many as I normally would have and was part of two classes.
It wasn't until my third thru-hike I made sure I have enough money to complete the trail.