I'm not sure that anyone but you can answer this one, there are too many variables.
It sounds like you don't have the income to be constantly bailing them out or it is something you would rather not do. There is no shame in that and I am not casting shadows.
You might want to sit down with them and look at what they are spending on. IE; do they have things that could be cut? Things like cell phone plans, for that matter any phones, and cable TV and internet are luxuries, They might be better off having a prepaid cell and nothing else and only broadcast TV, yes it does exist.
Is there a reason that a college student isn't paying for their own education?
If self employment isn't working for the wife she can get a job at least part time.
Like I said it is too complicated to answer here.