I have one piece of advice - one technique that I got from a cognitive behavioral therapist that helped me. It's pretty simple:
Pick a task you don't feel like doing. Set a timer. 10 or 15 minutes. Work on the task. Do not worry about the end result, or getting to a "good stopping point" or anything. When the timer stops, stop working on the task. Play another game or watch another YouTube video or something. When you feel like it, set the timer again and repeat.
The trick is that if you aren't worried about finishing the task you want to do, you can do the work without that feeling of discomfort and dread that makes you want to stop and distract yourself with something else.
The first time I did this technique, it was actually with dirty dishes and not work. I used to let them pile up because I just couldn't deal with it. I set a timer for 5 minutes and washed the dishes. It was a carefree experience. I walked away at the end, but then something funny happened - I soon wanted to go back for another 5 minutes. Pretty soon I finished the whole load of dishes and it wasn't unpleasant at all.