it feels like I’m fighting a level 102 creature when I’m only level 22
I love this place!
But in all seriously... I think everyone knows someone close who's had problems with drugs. Also, I think it's normal to experiment (dunno how old you are, guessing 18, 19 or something due to the fact you were talking about uni).
If you believe there is a problem, then more than likely there is, but it's not unusual for people to use extasy casually, same for coke. Normally it reduces as people get older (wiser?) but it's important for the people to be surrounded by "normal" people. It gives the idea of perspective.
All you can do it be there as someone who doesn't use, as a friend. For sure it'll be an influence. Don't start throwing bibles or anything though, that probs won't help.