You aren't alone; most people find themselves going along with the crowd from time to time, even when they know it's going to take them down the wrong path. But the Bible warns us against this: "Do not follow the crowd in doing wrong.... Do not pervert justice by siding with the crowd" (Exodus 23:2).
Have you ever asked yourself why you give in so easily, even when you know it's wrong? One reason may be that it simply seems easier to you to go along with the crowd instead of resisting them. Or perhaps you've never developed a strong inner sense of right and wrong. Instead of alarm bells going off inside of you (so to speak) when someone suggests doing something wrong, you hardly even think about it -- until it's too late. The Bible warns us not to be like those "whose consciences have been seared as with a hot iron" (1 Timothy 4:2).
But I suspect there may be another reason you give in so easily: you don't want to be rejected. Instead, you want everyone to like you -- and you're afraid that if you refuse to go along with them, they'll turn their backs on you. But do you really want that kind of friends?
Instead, I urge you to discover the greatest friend anyone can ever have: Jesus Christ. He loves you and accepts you just as you are, and He will never lead you astray. Invite Him into your life today, and then seek out other believers who will help you do what is right.