Guthrie was fined two weeks wages after he refused to travel for their trip to face Sunderland in December, but has now found himself back in Royals boss Brian McDermott's starting line-up.
Speaking to the club's official website, he said: "I'm really enjoying it and whatever has gone on in the past is clearly out of the window.
"I felt like I owed everyone not just a performance, but a bit of form to get us out of the hole we were in. I feel like I'm slowly doing that.
"I'm getting stronger in each game, and I got stronger as the game went on [at Newcastle].
|ROYALS TO STAY UP?|
|2/1||Reading are 2/1 with William Hill to avoid relegation from the Premier League|
"I was told that this club always gets stronger after Christmas and we've certainly done that. This is just the start of a run of games we need to put together."
"By no means we're out of trouble, but we're just looking at it game by game and it's a nice position that we've put ourselves in."
Reading have won four of their last five games, and will be looking for another victory when they face Sheffield United in the FA Cup on Saturday.