The 24-year-old joined Bournemouth on loan from Arsenal in August and has featured in eight league games since.
He played three league games for Arsenal in 2015-16 after breaking his leg, the latest in a run of injuries.
"I missed the fight of the Premier League, being in big games and making a difference for a team," said Wilshere.
"I wanted to feel that again and almost fall back in love with the game."
Wilshere has won 34 international caps in six years and has been recalled to the England squad by interim-boss Gareth Southgate for the World Cup qualifier with Scotland on Friday and friendly with Spain on Tuesday.
But he admits he has "been injured for too long" and wants to "prove" he still has the ability to play at the very top.
He seems to be doing that with his impressive form for Bournemouth.
He has created 14 chances for the Cherries in the league, a figure only bettered by £15m summer signing Jordon Ibe, who has made 15 following his move from Liverpool.
Having made his Arsenal debut aged 16 years and 256 days in 2008, Wilshere remains the youngest player to feature for the club in the Premier League, but he is aware his future at Emirates Stadium is uncertain.
"At the moment I am just trying to have a season where it puts me in a good position at the end of the year, that I have improved as a player and Arsenal want me back," he added.
"I could have stayed at Arsenal, been the player that comes on now and then off the bench, starts in the odd cup game, but I wanted more than that."
England midfielder Jack Wilshere says he needed a fresh challenge this season after "almost falling out of love with the game".