The left-back is out of contract in the summer and has been linked with varios clubs in the Premier League, including Stoke and West Brom.
The 23-year-old pulled out of the 1-1 draw with Wigan in Leeds' final league game of the season which had no bearing on promotion or relegation issues.
Taylor has been with Leeds since the age of nine and has made 104 first-team appearances since his debut in August 2011.
However, he told the club last summer he did not wish to speak about a new contract and then had a transfer request turned down.
Monk suggested Taylor's head had been turned by the interest reportedly shown in him from Premier League clubs.
"I understand he's very young, and we've tried to help him and guide him from within, but it's very difficult to get him fully committed," he said.
"Had he had some better advice from the outside, I think we would have seen a better Charlie Taylor this season and left on better terms, if that's what's going to happen. But that's over to the club and the player now.
"The club's stance on it is very strong. Hopefully he learns from the mistake he's made."