I have a similar story to share with you. My best friend was a pharm tech for about 4 years at Target (now CVS) while we were completing our undergrad together. He was so set on pharmacy school until one day he realized he didn't want to do that anymore. It probably didn't help that we live in a supersaturated state (California) and a handful of new pharmacy schools just opened up so it'll only get worse in the future. Anyways, long story short - he decided to become a physical therapist instead. He volunteered and shadowed PT for a year, and got into a competitive california PT program on his first try.
I think you made the right choice. Pharmacy is not the same as it used to be. The number of applications have dropped, standards have lowered, and schools are getting more expensive. There are a lot of statistics backing my claim. Meanwhile, nursing is a versatile career like you said. If you don't like acute care then you can switch to SNF or whatever you want. You can go back to school to become an educator, NP, CRNA, etc. The cost of nursing school is no where close to pharmacy school and the pay is comparable (at least in California). I was talking to an old neighbor of mine the other day, he is currently a pharmacist. He says hes been working a per diem job working 10-20 hours a pay check. He's having trouble finding any full time work as a pharmacist. This will only get worse in the future with the amount of new grads the U.S. is pumping out every year. Also, have fun as a pharmacist when Amazon
starts rolling out their own pharmacy plans.
Back to your question, I would just tell my parents. You can explain to them why you want to switch and give them the facts, but if they're anything like my parents - they won't care lol. But it's okay. They'll eventually come to their senses and agree with the choice that makes you the happiest.