I've always thought people on the Autisum spectrum were usually very honest, downright blunt.

If you can lie, connive and manipulate I tend to agree with your therapist and would conclude you are not autistic.

Autisum is a kind of different wiring, meaning you cannot feel for others, cannot 'put yourself in anothers shoes'
Lie-telling can be seen as a real-world application of an understanding of others’ minds
Autistic people not understand the minds of others so lying is very unlikely.

Liars and manipulators have narcissistic traits.