Earlier quoted context omitted.
>He doesn't get any preferential treatment from me [...] [knowing about his past] is valuable to me so I can put our relationship in right context. I don't understand how knowing about his past should matter if you're not going to behave differently towards him? That's like asking someone’s sex on an application form - if you're not going to discriminate why do you need to know.
To give you more detail. Addict is never really cured. Once you're through with addiction, the cravings are there for life. Whenever you need to release your steam the craving for drug kicks back in. My mentee is coping with that through writing, so sometimes he will not come to work on time - because he's setting his mind straight. So our agreement is that I don't care about his schedule - as long as his work is don…
However, it sounds like you are giving them preferential treatment. You say it's just different, but then if those differences aren't available to others they might also advantage it is a preferential treatment.
I guess one could argue it's not preferential in that you'd give the same assistance to another ex-addict.
Personally I don't think you have to help everyone just because you're helping someone, ie preferential treatment doesn't seem wrong to me a priori.