Although you may not have thought of it this way, I hope you'll be grateful you have friends who care about you this much. They see a side of life you don't see, and they want you to share in it.
Let me suggest three reasons why you need God. First, only Christ can give true meaning to your life. From what you say, you are living for one thing right now: to have a good time. And for a while that may seem to satisfy; the Bible says we sometimes may "enjoy the pleasures of sin for a short time" (Hebrews 11:25). But don't be deceived. Eventually, you will get bored, or unable to enjoy them—and what then? God put you here for a reason, and life's greatest joy comes from knowing His plan for our lives.
You also need Christ to help you every day. How else will you meet life's disappointments and heartaches? How else will you know which way to go when you have decisions to make? Where else will you go to find the inner strength to change your life and do what is right?
Finally, you need Christ for eternity. Someday we will all die and face God—and you are not prepared. But God loves you, and Christ died on the cross to take away your sins. Don't turn your back on Him, but by a simple prayer of faith confess your sins and ask Him into your life. Jesus' words are true: "I have come that they may have life, and have it to the full" (John 10:10).