Evil -

It's not insanity; rather, it's escapism. When we do harmful or distructive behaviors to ourselves (drugs, alcohol, harmful sex) it's because we are trying to bury the feelings that are making us feel bad.

It's not a teenage thing cause I did some of these up until I was 39 when I got sober.

Talk to a therapist to see if you can get to your feelings of lack of self worth and why you want to do this behavior. Your certainly not abnormal though - I think we all do this.

Tranquility