Vilanova underwent treatment for salivary gland cancer earlier this year in New York, where Guardiola had been taking a break from the game prior to his appointment at Bayern Munich.
However, despite being in the same city as his friend and former boss, Vilanova has insisted that Guardiola "wasn't there" for him during his recovery period.
"People aren't interested in personal matters, but Pep got it wrong and I'm surprised by his comments," he told reporters. "No-one on the board used my illness to attack him. The club tried to help me as much as possible.
"He visited me once in New York when I'd just arrived, but during my recovery from the operation I was there for two months and I didn't see him. He's my friend and I needed him, but he wasn't there for me. I would have done things differently."
Guardiola has previously denied claims that he made little attempt to see his former assistant at the Camp Nou.