I am also unable to drop top pairs that are beaten. I make a point to spot them, telling myself that in order to win a tournament I have to drop at least one top pair. It hasn't worked yet...
What does help a tad is asking yourself if you want to play a big pot here. Perhaps check back the turn instead we only have a pair, try and pick up tells
when he starts firing. Is this the best spot to get our money in, maybe wait for a more ideal/profitable spot to come.
Good luck!.. and if you manage to drop that top pair successfully without losing too much let us know.