The Germany international's controversial 37 million euro transfer between the two Bundesliga clubs was announced on the eve of Dortmund's Champions League semi-final tie with Real Madrid last April.
The timing of the announcement as well as the decision of one of their favourite players to leave for their fierce rivals saw Gotze go from hero to villain in the space of 24 hours and he expects a backlash when he returns to the Westfalenstadion on Saturday evening.
"It's going to be one of the toughest moments of my career," Gotze told Kicker magazine.
Gotze says he can understand the likely reaction he will receive from the near 80,000 Dortmund fans inside the Westfalenstadion, but he stands by his decision to join Bayern - a choice he made mainly for the fact Pep Guardiola had been announced as their new coach.
"At the end of the day, I've got to cope with it because it was my decision to leave," he said.