1-- The progressive makes clear that you are still not speaking to him.
2-- Yes.
The present perfect also does that. Especially for longer-lasting or permanent situations.
-I saw my father for the first time in 1988. I haven’t seen or spoken to him since then. Frankly I never wish to see nor speak to him again.
You might just have finished your period of not speaking to him, which would have been less likely if you’d used the continuous.
So, it would be better to say: I saw my father for the first time in 1988. I haven’t been seeing or speaking to him since then. Frankly, I never wish to see nor speak to him again.
Now what is the difference between: I haven’t spoken to him in years and I haven’t spoken to him for years.