OP I don't think I have much of value to say here, but I'm seeing so many comments from people who don't have a friggin clue about either international marriage, either emotionally or logistically, or clinical anxiety, so I just wanted to let you know you're not alone.
I'm British and I'm married to a Japanese. I have no choice but to live in Japan because the UKs spouse visa process is ridiculous and we don't even qualify to apply. I don't speak Japanese. I study it but it's going to be a fair while before I'm functional, so I'm pretty isolated. There are no other expats where we live, we're not in Tokyo. I have no degree and my job back at home was weirdly specific, I have no options here other than stay at home or teach English, and that often requires a degree so so far I only teach privately and I hate it.
I have suffered from clinical anxiety and depression all my adult life. Some times have been better than others. Getting help here doesn't seem like much of an option here, and I have no support network here outside of my partner who I obviously feel like a massive burden on, both emotionally and definitely financially. Sometimes I regret everything, other times it's worth it. The good times are increasing and it takes a while.
I won't ask specifics, and I know it varies from country to country, but I hope your partner's visa is issued soon, that should be the start of things looking up, and if they don't look up its ok to leave.
I'm still muddling through. Progress is very slow. I know none of this helps, but there are others like you and if you want to drop me a line and chat, feel free. Don't listen to those people who are calling you weak or who have no clue about the logistics of these things. International relationships can force us into these things, they can be very much all or nothing. And while it's nice to wait and see how things go that's not always a luxury we can afford. I never really grew up with strong views about marriage so I don't feel the same pressure in that regard, and I agree with those who have advised you to think of it merely as a paper marriage, and recognise that you do still have the right to leave if the relationship is making you miserable. I understand that believing this and challenging deep seated beliefs is tough and doesn't happen over night.
Please take care, and my inbox is right there.