Drugs in Prison? No visits - from AP

Hello.
My ex- partner is in prison for an offence involving drugs and he uses drugs in prison.
Why should I visit and play jolly olde happy families with his kids when he has no intention of addressing his problem? How can the parole board for example assess that he is bloody well remorseful towards his victims when he is using drugs in prison? His victims were robbed for drug money by the way. There is no victim empathy is there because basically he is laughing at everyone full on in the face.
If you test positive for drugs in prison, your visits should be sanctioned. It's disgusting that prisoners can easily get their hands on drugs in prison. Something has to give because some prisoners are even being released addicted to drugs when they never even took them before they were sent to prison.
I'm not an awkward person and would take the kids to see him but if he's smacked up, spiced up or pilled up, why the hell should I? You can rebuild relationships with druggies, they live in their own little unrealistic world with unrealistic friends who aren't really friends but just fellow junkies who have alternative benefit paydays. My ex forgot his son's birthday once but he never forgot when Alan, Craig or David's benefit pay day was! My God, addiction is so low!