I'm sorry I don't know the answer to your problem. But I certainly recognize it. I waited until the very last year I could finish my master's thesis to do it. My back had to be against the wall for me to finally make it happen. In my own defense I can say I had lots of other things going on... working full-time, helping to maintain a household, etc. But still... it would have been a lot better if I could have just knuckled down & done it to begin with instead of procrastinating for years... 7 to be exact as I recall.
By the time I finally decided I just had to finish my thesis, I was living in another part of the U.S. from where the graduate school I attended was located. When I wrote to the head of the department to ask about making the necessary arrangements, he wrote back (no personal computers back then) & one of the things he mentioned was that only a very small percentage of former students in my situation actually went on to finish their theses. (Yikes!) I am pleased to say, in the end, I helped to raise that percentage just a wee bit.
Perhaps a part of it was fear... fear that if I actually dug into it I'd find I couldn't do it... and then what? I'd be faced with the prospect of accepting I was just a failure. Part of it too was probably just there were a lot of other things I preferred to be doing rather than trying to write a thesis! After all... I had wood to chop for the winter!
Here are links to 8 articles, from Psych Central's archives, on the subjects of self-esteem, procrastination & self-sabotage. Perhaps there's something in these articles that can be of some help:
6 Tips to Improve Your Self-Esteem
Learn About Procrastination
Getting Help for Procrastination
Tips to Beat Procrastination
Procrastination: The Stalling Game Your Mind Loves to Play
https://psychcentral.com/blog/self-s...o-destruction/
https://blogs.psychcentral.com/nlp/2...self-sabotage/
https://blogs.psychcentral.com/imper...self-sabotage/