Why didn't Patsy kill Tony?

Why didn't Patsy kill Tony?

Tony had Patsy's brother, spoons, whacked because he thought spoons was spreading rumors about Tony and his mother.

It was also pretty obvious that Patsy knew that both Gigi and Tony were behind spoon's death.

Furthermore, there was that one scene where Patsy, drunk, was in Tony's backyard and was pointing his gun at him, ready to shoot him dead. However, he decides against it, and instead, piss in his pool.

Now my question is, why Patsy didn't shoot Tony? Or even never tried kill him again throughout the series? (If we believe the ending cut to black is Tony not dying or him not being killed by Patsy)