As others have said, consider just asking her to try another few months. 2 months isn’t a long time at all, and I’d imagine at least part of the reason she’s struggling for a job is COVID (ive worked once warehouses where half the people knew like 10 words in English, so that’s not the problem, a lot of them just don’t have room for more people right now even if they could use the help, because they legally need to be out of each other’s way). See if she can take language classes for free - a lot of cities offer this in normal times, no idea if anything is running with COVID and all. If her English is really non-existent try Duolingo and stuff like that, even if just for something to keep her mood up a bit.

Try to find a community of people from the same country so she can know more than 3 people in the area and make friends who’ve been in her situation.

If after you’ve tried some stuff she still wants to leave, let her go and just remind her of this if she ever asks for something like this again. Then get a roommate or move somewhere smaller and more affordable and start taking care of yourself again. Unfortunately stuff doesn’t always go to plan and you can’t tell other adults what to do, but try not to take it personally. She’s not rejecting you, this place just might not be for her.

My mom visits me in England once every 2 years and spends like 12/14 days in Spain or Italy because she hates how cold it is here and struggles to understand the accented English. It would be great if my family wanted to move here, but I’ve fully accepted that that’s probably never going to happen.

Good luck!