Freezing can change the texture a bit like you describe. Was the food otherwise OK?
With long term freezing the moisture can migrate out of the meat (freezer burn) and I use a FoodSaver (vacuum sealer) to minimize that.
Using frozen (raw) meat and freezing the resulting smoked meat are sometimes necessary. I can't eat eat everything I get from one batch in the smoker so freezing is a necessity. By the time I've reheated the smoked meat, it seems nearly as good as when it was fresh out of the smoker.