I've had negative motivation for many things, I have not been able to get around some of them but, for the ones I have been able to deal with, my most effective driver has been spite.

The best example I have off the top of my head is I had some pretty weird back pain / sciatic a nerve impingement symptoms. I also have hypermobile EDS. I went to a physical therapist to see if they could do anything and I researched the specific one that I wanted to go see because he was supposed to be really Hands-On and might help like with massage and scraping and not just send me home with exercises. He did the basic intake form with me and then punted me off to some less qualified less licensed assistant type person who did not listen to my complaints or pay attention to my chart at all. She had me do a couple movements and decided that my ass was weak. Those are the literal words she said. "Your ass is weak, that's the problem." My ass was not weak because I didn't have any muscle, my hip was not seated properly in the ball/socket joint at the time and therefore I had significant weakness in one leg. I told her that and that I knew that wasn't the problem, she refused to listen. She sent me home with a handful of exercises that I knew were not going to address the problem so I did the research for what would actually help for myself and did those exercises very specifically and not the ones she gave me out of spite. It worked of course and I went back the next session, in between I had also been able to put my hip back, and did all the things she asked me to very easily and she was just flabbergasted at how I could possibly have made so much progress. I told her "I said I had EDS and that my hip was out, that's why my leg didn't have much strength." This bitch had the audacity to say "you have h-EDS? I had no idea! I should have given you completely different exercises!". I of course never went back to that physical therapist's office but I continued to use spite to "prove this bitch wrong" and it was soooo motivating. That has been the best and longest run of dedicated strength training and cardio exercise I have ever started, all because the beginning motivation was "fuck you bitch! I know what's right and I'm not going to be gaslit into listening to your stupid fucking face when you won't listen to me and don't know what the fuck is going on."

I found that creating that sensation of "fuck you! I'm going to do the thing I know is right just to make you fucking angry and show you how wrong you fucking are" is the best way for me to turn negative motivation into positive motivation.

It's almost like you knowing what you should be doing is one polarity of a magnet and you knowimg you don't want to do it is the other polarity and they cancel each other out and you're left stationary, but somehow adding spite into the mix kind of flips the polarity of one or the other and gets you moving. I have even been able to do things out of spite of my own brain. Like, the negative self-talk voice in the back of my head is being such a cunt and I'm just like "you know what Steve!? (I named the negative voice in my head Steve) I'm going to get up and do the thing just to prove how fucking wrong you are because you are being such a stupid bitch right now!" I try not to think about it too hard because it works for me and I don't want to examine why and have it stop working so... do with that what you will.