Hi, I think I can somewhat relate to your situation. My (ex) boyfriend is now going through the same phase. We're both expats abroad and he hasn't really settled with the new expat lifestyle because we met when he was still very new in the country. Our relationship was intense and it was great in all aspects.
Anyway, just a couple of weeks back, he tells me he wants to be alone and find himself in this different lifestyle. Basically he wants to build new friendships and have experiences on his own. I know it's difficult for you as it was really difficult for me since we're both living in the same city, but really there's not much you can do. Just leave it be and hope for the best. Maybe you'll meet someone better, maybe you won't. Although, it's best for you to just leave things be. Who knows what will happen next. Maybe she'll come back, maybe she won't, but that's just life, isn't it?