I’m American, moved to the Czech Republic when I was in my late 20’s, loved it, witnessed other expats come and go. Some loved it, other hated it. I noticed it tended to be quite black or white: they loved it or hated it…
Here are two observations which may help:
1- If you are looking for to recreate your home country in France, just with better wine and baguettes, you’re going to have a bad time. It’s obviously going to be quite different. Some accept the bad with the good. Others constantly complain when France does not function like their home country… You have lived in France before, you speak the language, so you should be ok, assuming you enjoyed your time there.
2- I noticed that when couples moved, the key was the one who was not working. Let’s say the husband is working. He meets people through work, he travels, he has a life through work that keeps him active, ensures social networks, intellectual stimulation, etc. However, the wife, if she is just staying home, needs to actively find her raison d’etre. Either find her own job, or find a serious hobby, or something. If she is mainly at home, it’s harder.
Because what ultimately happened is all the shit jobs got dumped on the wife, because the husband was too busy with work. Moving to another country can be stressful, but there is also admin headache. You have to submit this form, go to this government office. Or even wait for the plumber who never shows up to fix a leak, or whatever…
Long story short, in my example above, the wife gets all the shit jobs, while the husband is flying around Europe for business meetings… And of course, the wife then starts to hate her life, hate her husband for forcing her into this situation, is jealous because he is loving the expat life while she is forced to sort out all the issues that come with living in a foreign country…
But if the wife did her own thing, if she had purpose, if she was very busy with something productive and stimulating, it helped a lot. I could always tell which expats would stay: if their wife was happy, I knew they would be there long term. If not, it was a 1 year excursion, max.
Good luck.
With no kids, no partner, I think you have lots of options. It sounds like you should move back to the USA, definitely. Sorry Australia didn’t work out for you.
Maybe you should look for jobs first? Then move based on what you find? Otherwise, I would guess you could move to a nice town, but then find a job that requires you to move again… Which probably isn’t ideal.
I briefly moved back to the Raleigh Durham area after being away for 20 years. But tbh, it’s not a great place if you are older and single. Most of the people there are married with kids, living in their planned suburbs, talking about school zoning issues and frequent flyer points…
Good luck.