First thing first, females are not supposed to build strong thick bubble nest, mine did.
Second they are not supposed to guard their nest, mine did.
Third they are more likely to eat all the eggs up, mine not only did not eat the eggs, she is taking care of them.
During spawning, if you are lucky you will have a female that will not eat the eggs but she will help with placing the eggs in the nest. Mine is more than lucky, she built her own nest and is taking care of the eggs like the father. Most likely these eggs are not fertilized, but I might be wrong, she might have store them in her mouth long enough for me to transfer her to the recuperating tank. Anyway this is truly amazing.
Female betta seen transferring eggs (and bubbles) back to the original nest after disturbance from water change