My mp3 player is probably about as random considering it can go from metal to trance to something like Il Divo or Sarah McLachlan to any variety of non-English music to movie soundtracks and so on and so forth. Honestly, I wouldn't worry about your psyche at all.

I don't really have advice for telling or not telling your friends, though. If they're the kind of friends who'd stop being your friend over your music tastes... I don't know. Hang in there. ♥