I second the idea about closure. Closure feels good. The problem is finding closure can take any time from hours to days for me. The "solution" is usually completely irrational.

I partially solved the problem by replacing the habit with physical exercise. Unfortunately light exercise won't do the trick, it has to be strenuous and last atleast for an hour.

Sometimes it seems I manage to simply suppress the habit, but maybe there are other replacement habits I'm not aware of.