I moved back to a great place on the mainland several years ago and only miss Honolulu every single day. We still have our place there and I get back as often as I can.
Most people that move to HI from the mainland relocate back to the mainland after an average of 7 years. I think it's mostly because they miss things on the mainland you can't get in Hawaii, and because making new friendships and kinships is tough. I've heard all of the tropes that locals are prejudiced against haoles (whites) but that's BS. I've never felt more kinship anywhere else. It's a shock to some mainlanders, but turns out that taking over a sovereign nation for business and military interests doesn't endear you to the local population. So it takes a long time to build trust. Hawaii is not your playground. It's a former nation with its own language, culture, religion, everything. So tread with humility and interest in Hawaiian life and history and you'll be welcomed in time.
You just have to embrace Hawaii on its own terms. You want barbecue? Better start liking Korean bbq. You want college football? Better love the Rainbow Warriors or get ready to watch games at 6am. You want culture? You get hula festivals and outrigger canoe competitions. So if you move there, you have to embrace it rather than dwell on the things you don't have there -- otherwise you'll get island fever and start looking for a way back.
pm me if you want more info