I’m lost

Im 20 years old. I left my country at 18 because I wanted to discover myself, I wanted to know what it was to work for things you want to archive without the help of my parents. I had everything back home, friends, family, my gf and my pets. I Thought leaving my first life would give me the tools I needed to become a “man”. And now after almost 3 years I dont know what im doing. I feel like I have lost myself along with my personality and my mind. Even tho I have friends here it just doesn’t feel the same, I still talk to my gf but distance is being tuff and I dont know if that relationship is gonna last any longer. Every time i finish my day routine is just me in my dark apartment, no one waiting and sometimes it just feels too heavy. My only distraction is my Muay thai class, thats when all my thoughts go away but after that I know im just gonna sit alone again in my kitchen. Is this thing normal? What can I do?