Hacker Has changed my Gmail password.

Hello,

My Gmail account has been hacked by someone I know. He has changed my password. He has done the same in the past also. Last time, I requested him to give me the password he changed after hacking.

I created this account in 2012. It is also connected with Google+. I have been playing Clash of Clans using the same account. Now, I want to delete this account because the hacking issue again and again.

Please help!