Crepe myrtle bloomed early, then filled out with lots of buds but didn't bloom.
Crepe Myrtle Blooming Issue
Certified GKH Gardening Expert
It has been a funny year for weather. Most plants will sacrifice their blossoms when under stress. If your tree experienced overly dry or overly wet conditions, it may have killed off its buds in order to preserve itself.
Another possibility is that the tree has pests and either the pests are stressing the tree (which leads to the buds not opening) or the pests are attacking the buds. As a precaution, I would recommend that you treat the tree with a pesticide. I personally like neem oil as it will kill the pests and will also treat for any fungus problems the tree may have. Plus, it is safe for people and pets as well as beneficial bugs.