You have a nice concept here, but the story seems a bit forced.
You have the workings to become a good writer. :)
I enjoy reading your ficlets

On the contrary, I feel that this story is well crafted. The agony of the main character punctuated by body language and a tumbling summary of all that came before is exceptionally real.
Formatting the speech a bit would make it easier to read, but I’ve found a greater tendency to overlook such things lately in search of good material.

I feel something similar with my own father. Your writing has really hit a nerve here.

I agree with Jae that formatting the speech would help, but it doesn’t bother me too much because it’s all stream of consciousness.

that…. That… Woman … “that” and “woman” shouldn’t be capitalised as they’re not new sentences.
Also you spelt "remember wrong in the third line up.

I hate therapists too.

I felt that his declaration of ‘I won’t bother you anymore’ didn’t match his accusations of his father forgetting his mom and that his father is responsible for her death, nor that he should not be flirting with the therapist.
You tried to make him have a grand exit, stumbling over his words about why he is angry, but it didn’t tie completely together.
He seems, to me, to be a whiny brat, but I’m not sure that’s what you were going for. :)