It's not like we start out as addicts. We all start to use for 'fun' and become addicted along the way.
Wanting it more is a sign that he is becoming more addicted. It's not because he somehow has increased his interest in having 'fun'.
His frequency in use has increased... another trademark sign of addiction.
His relationship is suffering because of his drug use... another sign of addiction.
He continues to use, despite you talking to him about it... another sign of addiction.
I would say ALL THE SIGNS POINT TO ADDICTION.