Muna had to flee her country (and thus her culture) for her own safety and along that journey also lost her mother and brother and landed in a country/culture that she needed to learn to navigate on her own and then everyone that she begins to trust and become close to die or disappear from her life. And that wore her down emotionally.
Her relationship with Yagiz, I thought was trying to connect back to Yasmin and making sure she is okay. And then Yagiz was able to provide a job for Muna which she knows is her connection to becoming a Swedish citizen which seemed the only goal she currently has in her life.