Why didn’t Anakin/Vader have a force bond with Ahsoka or Obi-Wan?

Difference between Force-bond and dyad in the force

We also need to explain the difference between a Force-bond and the rare Dyad in the Force before we can examine our theory.

With a Force-bond, the practitioners are two separate individuals within the Force acting on their own accord. Meanwhile, a Dyad in the Force is a partnership that acts as one entity. The only known example of this is Ben Solo, grandson of Darth Vader, and Rey, granddaughter of Sheev Palpatine.

Ben became aware of his bond with Rey on Takodana. After he captured the scavenger, his mind probe didn’t work on her. Though at the time this occurred, he had no idea that the dyad had formed between them.

As time went on, the connection between them became stronger, prompting them to form a complex relationship where both hated each other but understood the other. Rey started to confide in Ben while he stopped attempting to hide his misery and agony from her as she could sense it anyway.

Like her rival’s mother, Leia Organa, Rey could sense the light still shone in Ben, believing she could turn him back to the light. This would mirror how Kylo Ren’s uncle and former master, Luke Skywalker redeemed his grandfather Anakin all those years earlier.