Amid Sutil's legal troubles of 2011, he branded Briton Hamilton a "coward" for refusing to step up as a witness in his assault trial.
The German duly sat out 2012 but returned to F1 with Force India this year, and Hamilton promptly vowed to put their broken friendship back on track.
But, months later, Sutil said the Mercedes driver has done nothing.
"He is not able to speak -- maybe he is scared of me, I don't know," he told The National newspaper on Thursday at Spa.
"There is a time when people have to grow up and he hasn't done it," added Sutil.
He speculated that Hamilton's personality might be the victim of his success, having grown up in a council flat but then, while still a boy, signed by McLaren mentor Ron Dennis.
"Maybe," said Sutil.
"You suddenly go from being not interesting to being at the top and everyone loves you. You get the best from everywhere, you have a lot of money suddenly and this all affects your life.
"Hopefully, you wake up early and then you can sort out your life to be successful. Some people don't get that.
"If you have only a lot of possessions and no friends, you will be a lonely and sad man," Sutil concluded.