Follow your heart. If you think it is for you, then do it no matter what the current market is. When a field is in demand, many people will follow the track and more schools
will open up until the market is saturated like what are happening now in psychology (doctorate level), pharmacy, NPs in certain specialty, and even nurse anesthetist in my area. And it takes only a few years for the demand and supply curve to change. But if you follow your heart, you may still be ok (despite the competitive job market and poor pay).
Who know what will happen in the next few years wi
th the turf wars that is going on? Psychologists or even pharmacists may successfully lobby for some sorts of prescriptive authority or collaborative agreement and the demand for psych NP may decline subsequently. Or Psych NP may be able to expand the scope of practice. If you like mental health field, then go for it. If you are concerned about piling more debt, do not go to expensive online program, go to public school with cheapest tuition.