The 25-year-old was dealt a cruel blow in the build-up to Germany's World Cup campaign, tearing the ligaments in his left ankle during the 6-1 friendly win over Armenia just a week before the tournament began.
Reus was replaced in the squad by Shkodran Mustafi and was forced to watch on as his colleagues lifted the famous trophy with a 1-0 success over Argentina in the final last month.
On Monday, Reus was positive about how his recovery had been advancing.
"I'm even a bit ahead of schedule so [hopefully] it can continue like this," he told Kicker.
Reus also revealed the torment he endured while watching his compatriots clinch glory in South America.
"If one day before the departure to Brazil you get the bad news that you cannot fly with [the squad], it is very painful," he said.
"If you see how the World Cup ends, it hurts twice that I could not be there.
"For me, a dream has burst. The first few days were extremely hard. Luckily I had my family and friends around me."
At the time of the injury, Reus' recovery was expected to take three months, meaning he is unlikely to feature in Dortmund's first competitive fixture of the new campaign, the German Super Cup final against Bayern Munich on August 13.