I know the problem because I do it too. I think, for me at least, there is an element of closure that I need to avoid.

The logic, if you can call it that, goes something like this. If I call then either he doesn't have it (very small chance) and I win or he does have it (very high chance) and I loose, I'm an idiot BUT I know for sure he had it. If I fold I never know, I can't congratualte myself on folding because I'm not certain he had it.

That thinking is all wrong, I know that, but some times I don't give myself that extra few seconds I need to remind myself of it at the table.

A similar problem is the pre-flop raise in NLHE games. I have say JJ and raise 4-6xBB. Villain instantly goes over the top all-in. This is a fold, more often than not my JJ is beat but if I act on instinct rather than thinking I call it. If I'm going to play JJ for my whole stack then put on some pressure and go all-in myself first if not then for pity sake get out when it looks like you are beat!!!

I have no real answer other than to take a few more seconds. For me it's acting on instinct rather than logic that's the problem.