This is a very good document from a law school ...
So effectively, a trade body promoting services of their members ...
There is a lawyer somewhere that will tell you that any case you can imagine is worth pursuing. What they won't stress is that it's mostly worth pursuing for them, not you.
If winning the case would require that the whole fabric of society and family interactions be turned upside down, then it's not going to happen.
Save your money, spend it on something positive because unless you have a genuine claim based on some crime being committed or right being denied or violated, there is no case. Someone's family choosing to follow a belief system, however much we might think they shouldn't, is not something that a court is going to get involved in.
It comes back to the issue of whether the government should be involved forcing families or other members of a group to associate with each other. I can't think of anything quite so terrifying. The closest thing that approaches that would be child custody / visitation rights and look at what is involved in all that and how involved it is.