Curriculum, Credentials, Confidence.
Culinary school provides you with with a (hopefully) complete curriculum. What that means is that it will give you a base of knowledge about a lot of things, just a taste.
Depending on the circumstances, the credentials that graduating from culinary school can hold weight, but sometimes it's meaningless. Depends on the individual and circumstances.
For some people, Culinary School gives them a boost of confidence.
Is culinary school necessary? No. Not for everybody.
If your goal is to be a chef in a restaurant, then start working in a restaurant.
There are definitely concepts, methods and attitudes that I learned in culinary school that I still use today - and these are things that I wouldn't have picked up in the number of restaurants and jobs that I've worked since.
A good Culinary School will never be a waste, but what does the cost-benefit analysis tell you? That's an very personal process.
Factor in what your loan-payments are going to be, and what your salary will likely be. Work that into your budget and don't cut ti too close. If there's a decent chance that the loan payments will put you under water, then there's your financially-driven answer.
I'm not sure what you mean when you say you enjoy your 8 year career, but not like you love food. Please expound on that.