Moving to Sydney vs staying in the U.S.

Hi! So I've been living in Dallas for years and my boyfriend is from and lives in Sydney. We've been together for a little over a year and he's brought up twice recently indirectly that he wants me to move to Sydney. He said it's just an idea, and then said that he does like the idea of me being closer after doing long distance for a year now. He's successful and established in his job there. I didn't think our relationship would've lasted this long, but it has and if we're still together by the time I graduate, it would be about 2 and a half years together. He's very familiar with the U.S. and does come and visit

I'm in med school looking to be an internist (internal medicine) and he's suggested looking at Central Coast and the Hornsby area. Gosford, Nepean and other areas I've been suggested. I've been excited about the thought of moving and the adventure of moving to a new country. I love traveling and really have nothing tying me down here, but now I'm freaking out and feeling like I'd like to stay here or move back to California after graduating and finish studying for my medical licensing tests here. He also said that recently, the NSW health system has had some issues causing a number of doctors to resign, though says that the public system there is still infinitely better than in the U.S. and that Aus is in desperate need of doctors. He also thinks that the situation in the U.S. would get worse due to Trump, but I don't see it that way. I don't think residents are looking to leave the U.S. now that he's president

Also, maybe later, I could apply to a position in Sydney and surely, by that time we'd be living together. Would love to hear pros and cons of moving there vs staying. Things I should consider. I haven't been to Aus yet due to mostly school, but would like to visit maybe in the winter. I don't have any family I'd stay in the U.S. for. Mostly friends. I have a year and 4 months left of school, so have time and he's willing to wait for me to graduate. I've just been in the initial phases of research about the medical licensing tests there and hospitals I can apply to. Thank you for your help as I try to make this monumental decision of either moving or leaving a relationship I really don't want to. Open to any questions