This subject bothers me quiite a bit. I think because it all boils down to basic kindness. Forget empathy, forget understanding. Basic kindness says that when someone has been ligitimately wronged in one way or another you don't add insult to injury by figuratively spitting in their face.
Some parents/ In-laws get that and some don't. I've heard it go both ways. It is very interesting to see what parents will do when they find out that their kid has an addiction and is harming or breaking up the marriage because of it.
Everytime I hear about an in-laws reaction, it seems to fall under one of two categories. It should be noted that when I generally hear of examples that fall under these two categories, the relationship is going visably sour in some way. Separation, divorce, that kind of thing.
1) The in-laws find out that their kid has an addiction and is harming their marriage and they basically write off the addict's spouse. They blame the addict's spouse for the problem, maybe they claim that the addict's spouse is overreacting, isn't being sympathetic toward their addict kid. If separated the addict's spouse may suddenly not be invited to family parties any more, alternate stories will be told as to why you are having problems or are separated.
Or the opposite:
2) The in-laws find out that their kid has an addiction and is harming their marriage and the In-laws put their foot down. They support their kid, help him to get help, but they are straight forward with the fact that just because their kid messed his relationship up doesn't mean that they as his parents are going to miss out on their grandchildren or daughter(or son) in-law. They tell it how it really is, simultaneously interested in getting their kid help and also keeping a good relationship with the addict's spouse and children.
VERY different stories. I personally think that In-Laws who fall into the first category are more interested in appearances than health, and I think the In-laws in the second category are more interested in health than they are appearances.
I get that a parent will generally support their own child over their child-In-Law. I get that. But then truly support them. Don't skirt around the issues, don't cover them up, and don't mess up your relationship with your child-In-Law and grandchildren just for the sake of pretending that your kid doesn't have a problem.
I love hearing stories about category 2 In-laws, though it seems to me those are much fewer and in-between. But to me, that is strength. Strength is hugging the spouse that your child wronged and saying "I'm sorry my kid put you through this."
I think it's harmful to your addict kid to cover up their addiction an pretend that it isn't a big deal and that the spouse is over-reacting.
Do you have a child who is an addict?
Please fall under category 2.