I still feel homesick for the town I lived in longest, and I left there 13 years ago. It shaped who I am, so it's a significant thing.
I try to surround myself with it's identity instead now. I keep it's local paper in my Facebook newsfeed, stay in touch with old friends there, seek out paintings of the landscape and so on.
I'm consciously learning to like where I live now by seeking out little areas to explore and actively finding the good points, and appreciating that this is where my children have now put down roots so they come first.
But if my DP ever left me, and the children had flown the nest, I'm not convinced I'd stay here.
I'm here by circumstance, but making the best of it.
I'd move back to my hometown if that happened. Or maybe another place I've lived in that I loved.
But not a completely unknown place. So that confirms for me it's the memories I miss, and not the town.
Having said all that, you only get the one life, and whilst homesickness like grief cannot be overcome but can be handled with a little time, if something makes you intolerably unhappy, make the change. Make the neccessary sacrifices and make the change. You made a big sacrifice for your husband by leaving your life behind to follow him with his career, at some point he has to give back too.
You could afford to move back to your old town if the only obstacle is expense - you'd just have to consider if downsizing was A sacrifice you'd be prepared to make in order to live back there.
Be aware I've lived in over 22 towns, cities and hamlets though in my lifetime, so I'm not a sensible ambassador for homesickness or putting down roots
.