I think I may go ahead and cut my kids out of my will since they don't have any children.
Was this always intended?
This was not necessarily always intended, however lately I have been having some arguments with them.
It is your right to exclude your kids from your will. Though, I'd hope you would do so with good reason.
If they behave like this, maybe leaving them out of will is really a good idea. It would be much better for them in the future.
It is your choice to exclude whomever you want from your will. There is no need to feel bad about who you choose to leave your things to. This is the entire point of a will!