The best way I found of actually getting through the dread tasks is to cheat. Ask for help from someone else (presumably they do not have the mental block).

1. Identify the dread tasks.

2. Ask someone who cares (about you) to help you.

3. Do them together, with the other person not letting you get distracted.

For big tasks asking other people to help you chunk them also helps. After that avoid thinking about whole thing and just look at the small chunks.