Not sure you can make them understand unfortunately. I sometimes have people say stuff like that to me about my depression, PTSD and anxiety and experience the same frusteration of thinking 'well if i could just stop having these issues I would' so I can see where you are coming from, though I don't have any specific addiction issues have over indulged in/abused substances but not due to addiction.

You can certainly vent here though and will probably find some people who can understand...as for people who don't get it, sometimes you just have to accept that and still take care of yourself and your needs even if they don't get it....but that can be very frusterating and lack of support can make it more difficult, but one can also waste a lot of energy trying to get people to understand things they never can.