This is a similar path to the one I used for quitting drinking and smoking. Many attempts, relapses, failures, and more attempts until success sticks. It's been 4.5 years since I quit drinking, 6.5 months since I've quit smoking. The weight is the next thing on my list, and it will happen this year. Part of what set me off was a financial move. I saved up $1000, then spent on an awesome Bose PA system. Then a power cord to my macbook broke ($90), and I had to go to the doctor twice due to a spider bite ($100), and a weekly gig canceled. Ha! Murphy's Law.
When I had some money for an emergency, I had more confidence. I could walk around and say, "I can afford that if I wanted it. I could buy it right now!" That is a good feeling. I knew if my car broke down, or I had to leave town for a family emergency, I was covered. Without the emergency fund, I worried. I used to smoke when I was stressed, so now I eat. I should switch working out for eating while stressed, that way I could buy a new guitar and lose weight! lol
Now I'm back up to about $700 in savings, and getting more relaxed. Savings is not some magic key. The magic key is doing it, and not quitting. It's no different than quitting drinking or smoking; keep trying, and do not take it for granted once you get there.
By the way, I think the self sabotage is BS. I'm learning lessons. What to do, what not to do, and what works for me. It's better for the set back to occur early on; like a loss early on in the college football season. You get hungrier, and take are not as likely to take success for granted.