Porn is damaging him. There's a lot of info out there about the dangers of porn on erection quality. This is not about you being unattractive, but the slippery slope of watching too much porn and porn raising the bar so high, that no flesh and blood woman can compete. I wouldn't go as far to say he's an addict, but he's on the path to becoming one.

Masturbation with a tight grip will also effect sensitivity. He needs to stop masturbation for a while ( perhaps a couple of month) and when he does go back, a much lighter grip and ideally without using porn.