I've been living away from my family in Tokyo for the last five years.
I've been living and working in Tokyo on my own for the last five years even though my wife and kids live in Osaka.
ーI've been living away from my family in Tokyo for the last five years.
「この5年、私は東京で単身赴任をしています」
to live away from one's family を使って「単身赴任する」を表現できます。
ーI've been living and working in Tokyo on my own for the last five years even though my wife and kids live in Osaka.
「妻と子供は大阪に住んでいますが、この５年、私は東京で単身赴任をしています」
to live and work on one's own で「一人で暮らして働いている」
ご参考まで！
カナダ 
