The 25-year-old claims he was astonished to witness such a split following his World Cup success with Argentina.
Conte was sacked in March and Spurs would ultimately end the campaign in eighth with no European football for the first time since 2009/10.
"After winning the World Cup, I came back to Tottenham and the group were somewhat separate from the staff," Romero said.
"This is very difficult. My first match back was Aston Villa at home. We lost 2-0, that's where it all started.
"We'd win a game then we'd lose two. When things are divided and coaches and players are not pulling in the same direction it becomes very difficult.
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"But I'm the first to hold up my hands and take responsibility for the poor season we had.
"I'm not happy the season ended that way and I'm ready to repay the trust the club put in me and working to give my best."
Conte's assistant Cristian Stellini took charge midway through the season, only to also be given the boot after Spurs' 6-1 thrashing away to Newcastle one month into the role.
"The group were already in a bad way," continued Romero.
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"There was a divide and in a competition like the Premier League if you're not pulling in the same direction it's really tough.
"You saw that, not only against Newcastle but in the Liverpool game when they put three past us in the first 20 minutes and against Manchester United, when they were 2-0 up in the first half."
Romero says the mood inside the Spurs camp is totally different following the arrival of Ange Postecoglou, and believes the Australian will help them to get back to winning ways.
"It's a playing style Tottenham always had," said Romero.
"It's about taking more risks, trying to control games. We know the Premier League is a very tough league but we'll try to really impose ourselves on every game in the way we weren't able to last season.
"Obviously, I'm not happy with how last season ended for me. I'm the first to hold my hands up and say it wasn't the best season but when I got offers from other clubs to move away for this coming season, I said no because I want to have my best years here.
"I'm contracted to the club for many years. I really like the Premier League, I really like Tottenham and I want to be here for many more years to come.
"I always try to give absolutely everything on the field. I always try to repay that trust that the fans, the club and everyone else put in me. I'll try to come back in this coming season, by having good games so we can push the club as high up as possible."