Why do i change in environment?

[Yoseph]

a few months ago i spent a week at my friends haus with his family. this is the first time ive been away frm my home living in another home, but when i went there i really changed in the sense that i was more outgoing, more confident and more headstrong/straightforward with the things i did. then i came back home and im lazy, unmotivated and even get deppressed at times cuz i think so much. why does this happen. im 18 btw