New edition to an enabling/addicted family - What is my place?

Two years ago (age 38) I met my soul mate. We have been married one year, our relationship fits the first description of enabling, we are each better people in the world as a result of our support of one another, this is due I believe to deep levels of communication. I've never been happier, more on track or more productive in my life.

Soooooo, what's the problem? When I met my husbands family I thought I had really hit the jackpot, they seemed so wonderful and so close. Compared to my somewhat distant family I was very impressed by this. His Mom and Dad are still in love and still married (40 years) they are strong Mormons and have 5 sons. They are very loving people. But maybe too loving, their two oldest sons still live at home, one is very obese and reclusive/antisocial but does have a steady job (age 38). The other is charming but can't keep a job, is in massive debt, behind 40,000 in back child support payments and is a compulsive liar, (age 35) they are both heavy pot addicts.

Mom and Dad pay their way for everything, defend them and are basically in denial of the situation. Mom and Dad's financial situation is compromised due to covering for their sons all the time. This is not the only example of enabling in this family but just the biggest example.

My question is this. What is my place in this? I love these people, I am new to this family. I am normally the type to tell the truth and to shoot for open communication but when I have tried to bring this issue up with Mom, she becomes agitated and I do not want to harm the good relationship her and I have, but if I don't say something does that make me an enabler too?

My husband is so used to how his family is that his way of dealing with it to just let them be, and then to vent his feelings to me at those times the situation becomes frustrating for him.

These are wonderful people, it would be amazing to see them heal this damaging cycle and live to their potential but it may not be my place to suggest that openly.

What can I do?