I would be a great deal more worried about depression if someone was unable to cry. Frequent crying can be a sign of depression, or just a sign of stress. It can happen when you discuss something upsetting, even if your life is otherwise OK.
I am usually unable to conceal my emotions. As a result, I appear to be feeling them a lot more intensely than I am. I have, for example, been diagnosed with general anxiety disorder even though the anxiety I feel is normal and does not interfere with my life. Of course I can't compare it to what someone else feels; but the criterion of impairment is not met, and therefore the anxiety does not qualify me for a diagnosis.
If your therapist is assuming you show emotions in an average-NT style, s/he may be assuming that your feelings are more intense than your actions, as they would be for a neurotypical attempting to conceal his emotions. If, however, you are not concealing your emotions at all--either because you feel comfortable enough not to, because you have decided not to, or because you are unable to--then the therapist may be misinterpreting your actions.