The reason you can't swallow them is all in your head If you still can't swallow them crushed, then it is mental, not physical.

When you swallow them, try tilting your head to the side and slightly back, slightly.
The other thing you can do is swallow them with food. Tablets are smaller than most of the chewed amounts of food you swallow everytime you eat, so try chewing, then swallowing with the food.

Good luck ( I am assuming you tried taking them with water, not just trying to dry swallow them)