I am doing the same. I am just pointing out that we use different standards of 'proof'.
The only way I can assign an internal monologue of human emotions to you is (i) pattern match your external behavior with my own behavior in an emotional state (ii) take you on your word when you describe that your feelings, (iii) assume that all humans are roughly going to be the same.
With animals (ii) is not an option. It would not have been an option for Helen Keller too before a common language was established. Regarding (iii) it depends on where we draw the line where similarity ends, one can argue that there is a lot of shared physiology among say dolphins, us, elephants, primates dogs …
So believing that animals do not have internal monologue of emotions when they clearly show similar external manifestation is sourced more from human exceptionalism and having double standards for proofs.
We don't have the technology yet to listen into the internal monologues of anybody other than our own. All we have is evidence of external behavior and some physiological telemetry. What we conclude from these stems from what we want to believe. We have been wrong about our exceptionalism many times in history, so its not a very reliable guide.
By the way when I use the word 'you' its to draw attention to epistemological problem in the line of argument. Not that I disbelieve that you do have emotions.