what should i do?

Drink heavily. If you don't want to do long-term damage - perhaps see a psychologist? But who do you want to forget, and why, if that's not too personal a question? I've wanted to forget people before, but ultimately, if you forget, you don't learn anything. Life is suffering, my friend - but I think we can all learn a little at every turn and end up a lot wiser, if not necessarily happier!